Ca(La2Se3)4 crystallizes in the triclinic P1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one Se(2), one Se(21), one Se(3), one Se(4), one Se(6), one Se(7), one Se(8), and one Se(9) atom to form distorted CaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  an edgeedge with one La(11)Se8 hexagonal bipyramid,  an edgeedge with one La(16)Se8 hexagonal bipyramid, edges with two equivalent La(5)Se8 hexagonal bipyramids,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(7)Se8 hexagonal bipyramid. In the second Ca site, Ca(2) is bonded to one Se(10), one Se(12), one Se(13), one Se(15), one Se(16), one Se(19), one Se(22), and one Se(24) atom to form distorted CaSe8 hexagonal bipyramids that share  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(1)Se8 hexagonal bipyramid,  an edgeedge with one La(3)Se8 hexagonal bipyramid, edges with two equivalent La(9)Se8 hexagonal bipyramids,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. There are sixteen inequivalent La sites. In the first La site, La(1) is bonded to one Se(1), one Se(2), one Se(20), one Se(21), one Se(22), one Se(24), one Se(3), and one Se(7) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  an edgeedge with one Ca(2)Se8 hexagonal bipyramid,  an edgeedge with one La(6)Se8 hexagonal bipyramid, edges with two equivalent La(15)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid, and  a faceface with one La(5)Se8 hexagonal bipyramid. In the second La site, La(2) is bonded to one Se(1), one Se(2), one Se(23), one Se(24), one Se(3), one Se(4), one Se(5), and one Se(6) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(14)Se8 hexagonal bipyramids, edges with two equivalent La(4)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid, and  a faceface with one La(6)Se8 hexagonal bipyramid. In the third La site, La(3) is bonded to one Se(10), one Se(11), one Se(15), one Se(4), one Se(5), one Se(6), one Se(8), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one Ca(2)Se8 hexagonal bipyramid,  an edgeedge with one La(15)Se8 hexagonal bipyramid, edges with two equivalent La(6)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. In the fourth La site, La(4) is bonded to one Se(1), one Se(10), one Se(14), one Se(3), one Se(4), one Se(5), one Se(7), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(2)Se8 hexagonal bipyramids, edges with two equivalent La(7)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. In the fifth La site, La(5) is bonded to one Se(1), one Se(11), one Se(2), one Se(20), one Se(5), one Se(6), one Se(7), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  an edgeedge with one La(13)Se8 hexagonal bipyramid,  an edgeedge with one La(8)Se8 hexagonal bipyramid, edges with two equivalent Ca(1)Se8 hexagonal bipyramids,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(7)Se8 hexagonal bipyramid. In the sixth La site, La(6) is bonded to one Se(11), one Se(14), one Se(17), one Se(2), one Se(4), one Se(5), one Se(7), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(1)Se8 hexagonal bipyramid,  an edgeedge with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(3)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. In the seventh La site, La(7) is bonded to one Se(10), one Se(11), one Se(12), one Se(13), one Se(14), one Se(7), one Se(8), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(10)Se8 hexagonal bipyramids, edges with two equivalent La(4)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the eighth La site, La(8) is bonded to one Se(10), one Se(11), one Se(12), one Se(14), one Se(15), one Se(16), one Se(17), and one Se(5) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one La(16)Se8 hexagonal bipyramid,  an edgeedge with one La(5)Se8 hexagonal bipyramid, edges with two equivalent La(11)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the ninth La site, La(9) is bonded to one Se(12), one Se(13), one Se(14), one Se(16), one Se(17), one Se(18), one Se(19), and one Se(23) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(15)Se8 hexagonal bipyramid,  an edgeedge with one La(6)Se8 hexagonal bipyramid, edges with two equivalent Ca(2)Se8 hexagonal bipyramids,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. In the tenth La site, La(10) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), one Se(17), one Se(18), one Se(22), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(12)Se8 hexagonal bipyramids, edges with two equivalent La(7)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the eleventh La site, La(11) is bonded to one Se(10), one Se(13), one Se(14), one Se(15), one Se(17), one Se(19), one Se(4), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one Ca(1)Se8 hexagonal bipyramid,  an edgeedge with one La(13)Se8 hexagonal bipyramid, edges with two equivalent La(8)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the twelfth La site, La(12) is bonded to one Se(15), one Se(16), one Se(17), one Se(18), one Se(19), one Se(20), one Se(21), and one Se(22) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(10)Se8 hexagonal bipyramids, edges with two equivalent La(14)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the thirteenth La site, La(13) is bonded to one Se(1), one Se(13), one Se(18), one Se(19), one Se(20), one Se(22), one Se(23), and one Se(24) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one La(11)Se8 hexagonal bipyramid,  an edgeedge with one La(5)Se8 hexagonal bipyramid, edges with two equivalent La(16)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the fourteenth La site, La(14) is bonded to one Se(16), one Se(19), one Se(2), one Se(20), one Se(21), one Se(23), one Se(24), and one Se(6) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(12)Se8 hexagonal bipyramids, edges with two equivalent La(2)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. In the fifteenth La site, La(15) is bonded to one Se(1), one Se(18), one Se(20), one Se(21), one Se(23), one Se(3), one Se(6), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  an edgeedge with one La(3)Se8 hexagonal bipyramid,  an edgeedge with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(1)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid, and  a faceface with one La(5)Se8 hexagonal bipyramid. In the sixteenth La site, La(16) is bonded to one Se(12), one Se(16), one Se(18), one Se(21), one Se(22), one Se(23), one Se(24), and one Se(3) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one Ca(1)Se8 hexagonal bipyramid,  an edgeedge with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(13)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. There are twenty-four inequivalent Se sites. In the first Se site, Se(1) is bonded to one La(1), one La(13), one La(15), one La(2), one La(4), and one La(5) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(21)CaLa5 octahedra, corners with two equivalent Se(4)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra,  a faceface with one Se(20)La6 octahedra,  a faceface with one Se(23)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the second Se site, Se(2) is bonded to one Ca(1), one La(1), one La(14), one La(2), one La(5), and one La(6) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(9)CaLa5 octahedra, corners with two equivalent Se(23)La6 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-50°. In the third Se site, Se(3) is bonded to one Ca(1), one La(1), one La(15), one La(16), one La(2), and one La(4) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(20)La6 octahedra, corners with two equivalent Se(5)La6 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra, and  a faceface with one Se(1)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the fourth Se site, Se(4) is bonded to one Ca(1), one La(11), one La(2), one La(3), one La(4), and one La(6) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(1)La6 octahedra, corners with two equivalent Se(11)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the fifth Se site, Se(5) is bonded to one La(2), one La(3), one La(4), one La(5), one La(6), and one La(8) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(3)CaLa5 octahedra, corners with two equivalent Se(8)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the sixth Se site, Se(6) is bonded to one Ca(1), one La(14), one La(15), one La(2), one La(3), and one La(5) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(24)CaLa5 octahedra, corners with two equivalent Se(7)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(20)La6 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the seventh Se site, Se(7) is bonded to one Ca(1), one La(1), one La(4), one La(5), one La(6), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(10)CaLa5 octahedra, corners with two equivalent Se(6)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(14)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the eighth Se site, Se(8) is bonded to one Ca(1), one La(10), one La(11), one La(3), one La(6), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra, corners with two equivalent Se(12)CaLa5 octahedra, corners with two equivalent Se(5)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the ninth Se site, Se(9) is bonded to one Ca(1), one La(15), one La(3), one La(4), one La(5), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(2)CaLa5 octahedra, corners with two equivalent Se(14)La6 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the tenth Se site, Se(10) is bonded to one Ca(2), one La(11), one La(3), one La(4), one La(7), and one La(8) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra, corners with two equivalent Se(7)CaLa5 octahedra, corners with two equivalent Se(17)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-50°. In the eleventh Se site, Se(11) is bonded to one La(10), one La(3), one La(5), one La(6), one La(7), and one La(8) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(13)CaLa5 octahedra, corners with two equivalent Se(4)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the twelfth Se site, Se(12) is bonded to one Ca(2), one La(10), one La(16), one La(7), one La(8), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(19)CaLa5 octahedra, corners with two equivalent Se(8)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(11)La6 octahedra, and  a faceface with one Se(14)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the thirteenth Se site, Se(13) is bonded to one Ca(2), one La(10), one La(11), one La(13), one La(7), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(16)CaLa5 octahedra, corners with two equivalent Se(11)La6 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the fourteenth Se site, Se(14) is bonded to one La(11), one La(4), one La(6), one La(7), one La(8), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(15)CaLa5 octahedra, corners with two equivalent Se(9)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(17)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the fifteenth Se site, Se(15) is bonded to one Ca(2), one La(10), one La(11), one La(12), one La(3), and one La(8) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(14)La6 octahedra, corners with two equivalent Se(18)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra, and  a faceface with one Se(17)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the sixteenth Se site, Se(16) is bonded to one Ca(2), one La(12), one La(14), one La(16), one La(8), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(13)CaLa5 octahedra, corners with two equivalent Se(20)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the seventeenth Se site, Se(17) is bonded to one La(10), one La(11), one La(12), one La(6), one La(8), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(10)CaLa5 octahedra, corners with two equivalent Se(22)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(11)La6 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the eighteenth Se site, Se(18) is bonded to one La(10), one La(12), one La(13), one La(15), one La(16), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(15)CaLa5 octahedra, corners with two equivalent Se(24)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the nineteenth Se site, Se(19) is bonded to one Ca(2), one La(11), one La(12), one La(13), one La(14), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(12)CaLa5 octahedra, corners with two equivalent Se(21)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the twentieth Se site, Se(20) is bonded to one La(1), one La(12), one La(13), one La(14), one La(15), and one La(5) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(16)CaLa5 octahedra, corners with two equivalent Se(3)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra, and  a faceface with one Se(1)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the twenty-first Se site, Se(21) is bonded to one Ca(1), one La(1), one La(12), one La(14), one La(15), and one La(16) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(19)CaLa5 octahedra, corners with two equivalent Se(1)La6 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(18)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the twenty-second Se site, Se(22) is bonded to one Ca(2), one La(1), one La(10), one La(12), one La(13), and one La(16) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra, corners with two equivalent Se(17)La6 octahedra, corners with two equivalent Se(23)La6 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(18)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the twenty-third Se site, Se(23) is bonded to one La(13), one La(14), one La(15), one La(16), one La(2), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(2)CaLa5 octahedra, corners with two equivalent Se(22)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the twenty-fourth Se site, Se(24) is bonded to one Ca(2), one La(1), one La(13), one La(14), one La(16), and one La(2) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(6)CaLa5 octahedra, corners with two equivalent Se(18)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°.
Ca(La2Se3)4 crystallizes in the triclinic P1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one Se(2), one Se(21), one Se(3), one Se(4), one Se(6), one Se(7), one Se(8), and one Se(9) atom to form distorted CaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  an edgeedge with one La(11)Se8 hexagonal bipyramid,  an edgeedge with one La(16)Se8 hexagonal bipyramid, edges with two equivalent La(5)Se8 hexagonal bipyramids,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(7)Se8 hexagonal bipyramid. The Ca(1)-Se(2) bond length is 3.29 Å. The Ca(1)-Se(21) bond length is 3.04 Å. The Ca(1)-Se(3) bond length is 3.23 Å. The Ca(1)-Se(4) bond length is 3.25 Å. The Ca(1)-Se(6) bond length is 3.05 Å. The Ca(1)-Se(7) bond length is 3.23 Å. The Ca(1)-Se(8) bond length is 3.05 Å. The Ca(1)-Se(9) bond length is 3.04 Å. In the second Ca site, Ca(2) is bonded to one Se(10), one Se(12), one Se(13), one Se(15), one Se(16), one Se(19), one Se(22), and one Se(24) atom to form distorted CaSe8 hexagonal bipyramids that share  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(1)Se8 hexagonal bipyramid,  an edgeedge with one La(3)Se8 hexagonal bipyramid, edges with two equivalent La(9)Se8 hexagonal bipyramids,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. The Ca(2)-Se(10) bond length is 3.04 Å. The Ca(2)-Se(12) bond length is 3.05 Å. The Ca(2)-Se(13) bond length is 3.29 Å. The Ca(2)-Se(15) bond length is 3.23 Å. The Ca(2)-Se(16) bond length is 3.04 Å. The Ca(2)-Se(19) bond length is 3.23 Å. The Ca(2)-Se(22) bond length is 3.25 Å. The Ca(2)-Se(24) bond length is 3.05 Å. There are sixteen inequivalent La sites. In the first La site, La(1) is bonded to one Se(1), one Se(2), one Se(20), one Se(21), one Se(22), one Se(24), one Se(3), and one Se(7) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  an edgeedge with one Ca(2)Se8 hexagonal bipyramid,  an edgeedge with one La(6)Se8 hexagonal bipyramid, edges with two equivalent La(15)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid, and  a faceface with one La(5)Se8 hexagonal bipyramid. The La(1)-Se(1) bond length is 3.27 Å. The La(1)-Se(2) bond length is 3.22 Å. The La(1)-Se(20) bond length is 3.28 Å. The La(1)-Se(21) bond length is 3.01 Å. The La(1)-Se(22) bond length is 3.09 Å. The La(1)-Se(24) bond length is 3.19 Å. The La(1)-Se(3) bond length is 3.04 Å. The La(1)-Se(7) bond length is 3.05 Å. In the second La site, La(2) is bonded to one Se(1), one Se(2), one Se(23), one Se(24), one Se(3), one Se(4), one Se(5), and one Se(6) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(14)Se8 hexagonal bipyramids, edges with two equivalent La(4)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid, and  a faceface with one La(6)Se8 hexagonal bipyramid. The La(2)-Se(1) bond length is 3.08 Å. The La(2)-Se(2) bond length is 3.06 Å. The La(2)-Se(23) bond length is 3.24 Å. The La(2)-Se(24) bond length is 3.25 Å. The La(2)-Se(3) bond length is 3.06 Å. The La(2)-Se(4) bond length is 3.22 Å. The La(2)-Se(5) bond length is 3.23 Å. The La(2)-Se(6) bond length is 3.07 Å. In the third La site, La(3) is bonded to one Se(10), one Se(11), one Se(15), one Se(4), one Se(5), one Se(6), one Se(8), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one Ca(2)Se8 hexagonal bipyramid,  an edgeedge with one La(15)Se8 hexagonal bipyramid, edges with two equivalent La(6)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. The La(3)-Se(10) bond length is 3.22 Å. The La(3)-Se(11) bond length is 3.06 Å. The La(3)-Se(15) bond length is 3.07 Å. The La(3)-Se(4) bond length is 3.26 Å. The La(3)-Se(5) bond length is 3.07 Å. The La(3)-Se(6) bond length is 3.06 Å. The La(3)-Se(8) bond length is 3.22 Å. The La(3)-Se(9) bond length is 3.22 Å. In the fourth La site, La(4) is bonded to one Se(1), one Se(10), one Se(14), one Se(3), one Se(4), one Se(5), one Se(7), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(2)Se8 hexagonal bipyramids, edges with two equivalent La(7)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. The La(4)-Se(1) bond length is 3.23 Å. The La(4)-Se(10) bond length is 3.26 Å. The La(4)-Se(14) bond length is 3.20 Å. The La(4)-Se(3) bond length is 3.21 Å. The La(4)-Se(4) bond length is 3.07 Å. The La(4)-Se(5) bond length is 3.07 Å. The La(4)-Se(7) bond length is 3.07 Å. The La(4)-Se(9) bond length is 3.07 Å. In the fifth La site, La(5) is bonded to one Se(1), one Se(11), one Se(2), one Se(20), one Se(5), one Se(6), one Se(7), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  an edgeedge with one La(13)Se8 hexagonal bipyramid,  an edgeedge with one La(8)Se8 hexagonal bipyramid, edges with two equivalent Ca(1)Se8 hexagonal bipyramids,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid, and  a faceface with one La(7)Se8 hexagonal bipyramid. The La(5)-Se(1) bond length is 3.23 Å. The La(5)-Se(11) bond length is 3.07 Å. The La(5)-Se(2) bond length is 3.07 Å. The La(5)-Se(20) bond length is 3.04 Å. The La(5)-Se(5) bond length is 3.23 Å. The La(5)-Se(6) bond length is 3.24 Å. The La(5)-Se(7) bond length is 3.05 Å. The La(5)-Se(9) bond length is 3.26 Å. In the sixth La site, La(6) is bonded to one Se(11), one Se(14), one Se(17), one Se(2), one Se(4), one Se(5), one Se(7), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(1)Se8 hexagonal bipyramid,  an edgeedge with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(3)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. The La(6)-Se(11) bond length is 3.24 Å. The La(6)-Se(14) bond length is 3.23 Å. The La(6)-Se(17) bond length is 3.08 Å. The La(6)-Se(2) bond length is 3.03 Å. The La(6)-Se(4) bond length is 3.06 Å. The La(6)-Se(5) bond length is 3.24 Å. The La(6)-Se(7) bond length is 3.25 Å. The La(6)-Se(8) bond length is 3.07 Å. In the seventh La site, La(7) is bonded to one Se(10), one Se(11), one Se(12), one Se(13), one Se(14), one Se(7), one Se(8), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(10)Se8 hexagonal bipyramids, edges with two equivalent La(4)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(7)-Se(10) bond length is 3.07 Å. The La(7)-Se(11) bond length is 3.07 Å. The La(7)-Se(12) bond length is 3.29 Å. The La(7)-Se(13) bond length is 3.23 Å. The La(7)-Se(14) bond length is 3.07 Å. The La(7)-Se(7) bond length is 3.20 Å. The La(7)-Se(8) bond length is 3.06 Å. The La(7)-Se(9) bond length is 3.21 Å. In the eighth La site, La(8) is bonded to one Se(10), one Se(11), one Se(12), one Se(14), one Se(15), one Se(16), one Se(17), and one Se(5) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one La(16)Se8 hexagonal bipyramid,  an edgeedge with one La(5)Se8 hexagonal bipyramid, edges with two equivalent La(11)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(8)-Se(10) bond length is 3.20 Å. The La(8)-Se(11) bond length is 3.25 Å. The La(8)-Se(12) bond length is 3.25 Å. The La(8)-Se(14) bond length is 3.07 Å. The La(8)-Se(15) bond length is 3.29 Å. The La(8)-Se(16) bond length is 3.06 Å. The La(8)-Se(17) bond length is 3.10 Å. The La(8)-Se(5) bond length is 3.07 Å. In the ninth La site, La(9) is bonded to one Se(12), one Se(13), one Se(14), one Se(16), one Se(17), one Se(18), one Se(19), and one Se(23) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  an edgeedge with one La(15)Se8 hexagonal bipyramid,  an edgeedge with one La(6)Se8 hexagonal bipyramid, edges with two equivalent Ca(2)Se8 hexagonal bipyramids,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(8)Se8 hexagonal bipyramid. The La(9)-Se(12) bond length is 3.24 Å. The La(9)-Se(13) bond length is 3.07 Å. The La(9)-Se(14) bond length is 3.04 Å. The La(9)-Se(16) bond length is 3.26 Å. The La(9)-Se(17) bond length is 3.23 Å. The La(9)-Se(18) bond length is 3.23 Å. The La(9)-Se(19) bond length is 3.05 Å. The La(9)-Se(23) bond length is 3.07 Å. In the tenth La site, La(10) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), one Se(17), one Se(18), one Se(22), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(12)Se8 hexagonal bipyramids, edges with two equivalent La(7)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(10)-Se(11) bond length is 3.24 Å. The La(10)-Se(12) bond length is 3.07 Å. The La(10)-Se(13) bond length is 3.06 Å. The La(10)-Se(15) bond length is 3.06 Å. The La(10)-Se(17) bond length is 3.08 Å. The La(10)-Se(18) bond length is 3.23 Å. The La(10)-Se(22) bond length is 3.22 Å. The La(10)-Se(8) bond length is 3.25 Å. In the eleventh La site, La(11) is bonded to one Se(10), one Se(13), one Se(14), one Se(15), one Se(17), one Se(19), one Se(4), and one Se(8) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one Ca(1)Se8 hexagonal bipyramid,  an edgeedge with one La(13)Se8 hexagonal bipyramid, edges with two equivalent La(8)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(3)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid,  a faceface with one La(6)Se8 hexagonal bipyramid,  a faceface with one La(7)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(11)-Se(10) bond length is 3.01 Å. The La(11)-Se(13) bond length is 3.22 Å. The La(11)-Se(14) bond length is 3.28 Å. The La(11)-Se(15) bond length is 3.04 Å. The La(11)-Se(17) bond length is 3.27 Å. The La(11)-Se(19) bond length is 3.05 Å. The La(11)-Se(4) bond length is 3.09 Å. The La(11)-Se(8) bond length is 3.19 Å. In the twelfth La site, La(12) is bonded to one Se(15), one Se(16), one Se(17), one Se(18), one Se(19), one Se(20), one Se(21), and one Se(22) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(10)Se8 hexagonal bipyramids, edges with two equivalent La(14)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(11)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(8)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(12)-Se(15) bond length is 3.20 Å. The La(12)-Se(16) bond length is 2.97 Å. The La(12)-Se(17) bond length is 3.19 Å. The La(12)-Se(18) bond length is 3.04 Å. The La(12)-Se(19) bond length is 3.16 Å. The La(12)-Se(20) bond length is 3.29 Å. The La(12)-Se(21) bond length is 3.24 Å. The La(12)-Se(22) bond length is 3.11 Å. In the thirteenth La site, La(13) is bonded to one Se(1), one Se(13), one Se(18), one Se(19), one Se(20), one Se(22), one Se(23), and one Se(24) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one La(11)Se8 hexagonal bipyramid,  an edgeedge with one La(5)Se8 hexagonal bipyramid, edges with two equivalent La(16)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(13)-Se(1) bond length is 3.08 Å. The La(13)-Se(13) bond length is 3.03 Å. The La(13)-Se(18) bond length is 3.24 Å. The La(13)-Se(19) bond length is 3.25 Å. The La(13)-Se(20) bond length is 3.23 Å. The La(13)-Se(22) bond length is 3.06 Å. The La(13)-Se(23) bond length is 3.24 Å. The La(13)-Se(24) bond length is 3.07 Å. In the fourteenth La site, La(14) is bonded to one Se(16), one Se(19), one Se(2), one Se(20), one Se(21), one Se(23), one Se(24), and one Se(6) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(11)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(3)Se8 hexagonal bipyramid,  a cornercorner with one La(6)Se8 hexagonal bipyramid,  a cornercorner with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(12)Se8 hexagonal bipyramids, edges with two equivalent La(2)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(5)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(14)-Se(16) bond length is 3.26 Å. The La(14)-Se(19) bond length is 3.23 Å. The La(14)-Se(2) bond length is 3.24 Å. The La(14)-Se(20) bond length is 3.03 Å. The La(14)-Se(21) bond length is 3.10 Å. The La(14)-Se(23) bond length is 3.00 Å. The La(14)-Se(24) bond length is 3.15 Å. The La(14)-Se(6) bond length is 3.21 Å. In the fifteenth La site, La(15) is bonded to one Se(1), one Se(18), one Se(20), one Se(21), one Se(23), one Se(3), one Se(6), and one Se(9) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(1)Se8 hexagonal bipyramid,  a cornercorner with one La(10)Se8 hexagonal bipyramid,  a cornercorner with one La(13)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(16)Se8 hexagonal bipyramid,  a cornercorner with one La(2)Se8 hexagonal bipyramid,  a cornercorner with one La(5)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  an edgeedge with one La(3)Se8 hexagonal bipyramid,  an edgeedge with one La(9)Se8 hexagonal bipyramid, edges with two equivalent La(1)Se8 hexagonal bipyramids,  a faceface with one Ca(1)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(13)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(16)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid,  a faceface with one La(4)Se8 hexagonal bipyramid, and  a faceface with one La(5)Se8 hexagonal bipyramid. The La(15)-Se(1) bond length is 3.10 Å. The La(15)-Se(18) bond length is 3.07 Å. The La(15)-Se(20) bond length is 3.07 Å. The La(15)-Se(21) bond length is 3.20 Å. The La(15)-Se(23) bond length is 3.25 Å. The La(15)-Se(3) bond length is 3.29 Å. The La(15)-Se(6) bond length is 3.25 Å. The La(15)-Se(9) bond length is 3.06 Å. In the sixteenth La site, La(16) is bonded to one Se(12), one Se(16), one Se(18), one Se(21), one Se(22), one Se(23), one Se(24), and one Se(3) atom to form distorted LaSe8 hexagonal bipyramids that share  a cornercorner with one Ca(2)Se8 hexagonal bipyramid,  a cornercorner with one La(1)Se8 hexagonal bipyramid,  a cornercorner with one La(12)Se8 hexagonal bipyramid,  a cornercorner with one La(14)Se8 hexagonal bipyramid,  a cornercorner with one La(15)Se8 hexagonal bipyramid,  a cornercorner with one La(4)Se8 hexagonal bipyramid,  a cornercorner with one La(7)Se8 hexagonal bipyramid,  a cornercorner with one La(9)Se8 hexagonal bipyramid,  an edgeedge with one Ca(1)Se8 hexagonal bipyramid,  an edgeedge with one La(8)Se8 hexagonal bipyramid, edges with two equivalent La(13)Se8 hexagonal bipyramids,  a faceface with one Ca(2)Se8 hexagonal bipyramid,  a faceface with one La(1)Se8 hexagonal bipyramid,  a faceface with one La(10)Se8 hexagonal bipyramid,  a faceface with one La(12)Se8 hexagonal bipyramid,  a faceface with one La(14)Se8 hexagonal bipyramid,  a faceface with one La(15)Se8 hexagonal bipyramid,  a faceface with one La(2)Se8 hexagonal bipyramid, and  a faceface with one La(9)Se8 hexagonal bipyramid. The La(16)-Se(12) bond length is 3.06 Å. The La(16)-Se(16) bond length is 3.22 Å. The La(16)-Se(18) bond length is 3.07 Å. The La(16)-Se(21) bond length is 3.22 Å. The La(16)-Se(22) bond length is 3.26 Å. The La(16)-Se(23) bond length is 3.06 Å. The La(16)-Se(24) bond length is 3.22 Å. The La(16)-Se(3) bond length is 3.07 Å. There are twenty-four inequivalent Se sites. In the first Se site, Se(1) is bonded to one La(1), one La(13), one La(15), one La(2), one La(4), and one La(5) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(21)CaLa5 octahedra, corners with two equivalent Se(4)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra,  a faceface with one Se(20)La6 octahedra,  a faceface with one Se(23)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the second Se site, Se(2) is bonded to one Ca(1), one La(1), one La(14), one La(2), one La(5), and one La(6) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(9)CaLa5 octahedra, corners with two equivalent Se(23)La6 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-50°. In the third Se site, Se(3) is bonded to one Ca(1), one La(1), one La(15), one La(16), one La(2), and one La(4) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(20)La6 octahedra, corners with two equivalent Se(5)La6 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra, and  a faceface with one Se(1)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the fourth Se site, Se(4) is bonded to one Ca(1), one La(11), one La(2), one La(3), one La(4), and one La(6) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(1)La6 octahedra, corners with two equivalent Se(11)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the fifth Se site, Se(5) is bonded to one La(2), one La(3), one La(4), one La(5), one La(6), and one La(8) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(3)CaLa5 octahedra, corners with two equivalent Se(8)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the sixth Se site, Se(6) is bonded to one Ca(1), one La(14), one La(15), one La(2), one La(3), and one La(5) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(24)CaLa5 octahedra, corners with two equivalent Se(7)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(20)La6 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the seventh Se site, Se(7) is bonded to one Ca(1), one La(1), one La(4), one La(5), one La(6), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(10)CaLa5 octahedra, corners with two equivalent Se(6)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(14)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the eighth Se site, Se(8) is bonded to one Ca(1), one La(10), one La(11), one La(3), one La(6), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra, corners with two equivalent Se(12)CaLa5 octahedra, corners with two equivalent Se(5)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the ninth Se site, Se(9) is bonded to one Ca(1), one La(15), one La(3), one La(4), one La(5), and one La(7) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(2)CaLa5 octahedra, corners with two equivalent Se(14)La6 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(11)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the tenth Se site, Se(10) is bonded to one Ca(2), one La(11), one La(3), one La(4), one La(7), and one La(8) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra, corners with two equivalent Se(7)CaLa5 octahedra, corners with two equivalent Se(17)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-50°. In the eleventh Se site, Se(11) is bonded to one La(10), one La(3), one La(5), one La(6), one La(7), and one La(8) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(13)CaLa5 octahedra, corners with two equivalent Se(4)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra,  a faceface with one Se(9)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(5)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the twelfth Se site, Se(12) is bonded to one Ca(2), one La(10), one La(16), one La(7), one La(8), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(19)CaLa5 octahedra, corners with two equivalent Se(8)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(11)La6 octahedra, and  a faceface with one Se(14)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-51°. In the thirteenth Se site, Se(13) is bonded to one Ca(2), one La(10), one La(11), one La(13), one La(7), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(16)CaLa5 octahedra, corners with two equivalent Se(11)La6 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the fourteenth Se site, Se(14) is bonded to one La(11), one La(4), one La(6), one La(7), one La(8), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(15)CaLa5 octahedra, corners with two equivalent Se(9)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(4)CaLa5 octahedra,  a faceface with one Se(7)CaLa5 octahedra, and  a faceface with one Se(17)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the fifteenth Se site, Se(15) is bonded to one Ca(2), one La(10), one La(11), one La(12), one La(3), and one La(8) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra, corners with two equivalent Se(14)La6 octahedra, corners with two equivalent Se(18)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(11)La6 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(10)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(8)CaLa5 octahedra, and  a faceface with one Se(17)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the sixteenth Se site, Se(16) is bonded to one Ca(2), one La(12), one La(14), one La(16), one La(8), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(13)CaLa5 octahedra, corners with two equivalent Se(20)La6 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(17)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the seventeenth Se site, Se(17) is bonded to one La(10), one La(11), one La(12), one La(6), one La(8), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(10)CaLa5 octahedra, corners with two equivalent Se(22)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(4)CaLa5 octahedra,  an edgeedge with one Se(8)CaLa5 octahedra,  an edgeedge with one Se(5)La6 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(11)La6 octahedra,  a faceface with one Se(14)La6 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the eighteenth Se site, Se(18) is bonded to one La(10), one La(12), one La(13), one La(15), one La(16), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(15)CaLa5 octahedra, corners with two equivalent Se(24)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the nineteenth Se site, Se(19) is bonded to one Ca(2), one La(11), one La(12), one La(13), one La(14), and one La(9) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(12)CaLa5 octahedra, corners with two equivalent Se(21)CaLa5 octahedra,  an edgeedge with one Se(10)CaLa5 octahedra,  an edgeedge with one Se(15)CaLa5 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(14)La6 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(13)CaLa5 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(17)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the twentieth Se site, Se(20) is bonded to one La(1), one La(12), one La(13), one La(14), one La(15), and one La(5) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(16)CaLa5 octahedra, corners with two equivalent Se(3)CaLa5 octahedra,  an edgeedge with one Se(2)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(18)La6 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(21)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra, and  a faceface with one Se(1)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-52°. In the twenty-first Se site, Se(21) is bonded to one Ca(1), one La(1), one La(12), one La(14), one La(15), and one La(16) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(12)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(6)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra, corners with two equivalent Se(19)CaLa5 octahedra, corners with two equivalent Se(1)La6 octahedra,  an edgeedge with one Se(22)CaLa5 octahedra,  an edgeedge with one Se(24)CaLa5 octahedra,  an edgeedge with one Se(6)CaLa5 octahedra,  an edgeedge with one Se(7)CaLa5 octahedra,  an edgeedge with one Se(9)CaLa5 octahedra,  an edgeedge with one Se(23)La6 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra,  a faceface with one Se(18)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 15-52°. In the twenty-second Se site, Se(22) is bonded to one Ca(2), one La(1), one La(10), one La(12), one La(13), and one La(16) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(13)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(2)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(8)CaLa5 octahedra,  a cornercorner with one Se(11)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra, corners with two equivalent Se(17)La6 octahedra, corners with two equivalent Se(23)La6 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  a faceface with one Se(12)CaLa5 octahedra,  a faceface with one Se(15)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(18)La6 octahedra, and  a faceface with one Se(20)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°. In the twenty-third Se site, Se(23) is bonded to one La(13), one La(14), one La(15), one La(16), one La(2), and one La(9) atom to form distorted SeLa6 octahedra that share  a cornercorner with one Se(19)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(24)CaLa5 octahedra,  a cornercorner with one Se(3)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(9)CaLa5 octahedra,  a cornercorner with one Se(14)La6 octahedra,  a cornercorner with one Se(17)La6 octahedra,  a cornercorner with one Se(18)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(2)CaLa5 octahedra, corners with two equivalent Se(22)CaLa5 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(19)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(3)CaLa5 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(16)CaLa5 octahedra,  a faceface with one Se(24)CaLa5 octahedra,  a faceface with one Se(6)CaLa5 octahedra,  a faceface with one Se(1)La6 octahedra, and  a faceface with one Se(18)La6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the twenty-fourth Se site, Se(24) is bonded to one Ca(2), one La(1), one La(13), one La(14), one La(16), and one La(2) atom to form distorted SeCaLa5 octahedra that share  a cornercorner with one Se(10)CaLa5 octahedra,  a cornercorner with one Se(15)CaLa5 octahedra,  a cornercorner with one Se(16)CaLa5 octahedra,  a cornercorner with one Se(21)CaLa5 octahedra,  a cornercorner with one Se(22)CaLa5 octahedra,  a cornercorner with one Se(4)CaLa5 octahedra,  a cornercorner with one Se(7)CaLa5 octahedra,  a cornercorner with one Se(1)La6 octahedra,  a cornercorner with one Se(20)La6 octahedra,  a cornercorner with one Se(23)La6 octahedra,  a cornercorner with one Se(5)La6 octahedra, corners with two equivalent Se(6)CaLa5 octahedra, corners with two equivalent Se(18)La6 octahedra,  an edgeedge with one Se(12)CaLa5 octahedra,  an edgeedge with one Se(13)CaLa5 octahedra,  an edgeedge with one Se(16)CaLa5 octahedra,  an edgeedge with one Se(21)CaLa5 octahedra,  an edgeedge with one Se(1)La6 octahedra,  an edgeedge with one Se(20)La6 octahedra,  a faceface with one Se(19)CaLa5 octahedra,  a faceface with one Se(2)CaLa5 octahedra,  a faceface with one Se(22)CaLa5 octahedra,  a faceface with one Se(3)CaLa5 octahedra, and  a faceface with one Se(23)La6 octahedra. The corner-sharing octahedral tilt angles range from 17-51°.