Pr8(BCl)7 crystallizes in the triclinic P-1 space group. There are eight inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 7-coordinate geometry to one B(1), one B(4), one B(5), one B(6), one B(7), one Cl(1), one Cl(2), one Cl(3), and one Cl(5) atom. In the second Pr site, Pr(2) is bonded in a 7-coordinate geometry to one B(2), one B(3), one B(4), one B(5), one B(6), one Cl(1), one Cl(2), one Cl(7), and one Cl(8) atom. In the third Pr site, Pr(3) is bonded in a 6-coordinate geometry to one B(4), one Cl(3), one Cl(6), one Cl(7), and two equivalent Cl(4) atoms. In the fourth Pr site, Pr(4) is bonded in a 7-coordinate geometry to one B(5), one Cl(4), one Cl(7), two equivalent Cl(3), and two equivalent Cl(6) atoms. In the fifth Pr site, Pr(5) is bonded in a 7-coordinate geometry to one B(1), one B(4), one B(5), one B(6), one B(7), one Cl(1), one Cl(2), one Cl(4), and one Cl(6) atom. In the sixth Pr site, Pr(6) is bonded in a 9-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(6), one Cl(1), one Cl(5), and one Cl(8) atom. In the seventh Pr site, Pr(7) is bonded in a 7-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(7), one Cl(2), one Cl(5), and one Cl(8) atom. In the eighth Pr site, Pr(8) is bonded in a 9-coordinate geometry to one B(2), one B(3), one B(4), one B(5), one B(6), one Cl(1), one Cl(2), one Cl(4), and one Cl(6) atom. There are seven inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(5), two equivalent Pr(6), two equivalent Pr(7), one B(2), one B(6), and one B(7) atom. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Pr(2), one Pr(8), two equivalent Pr(6), two equivalent Pr(7), one B(1), one B(3), and one B(6) atom. In the third B site, B(3) is bonded to one Pr(2), one Pr(8), two equivalent Pr(7), one B(2), one B(4), and one B(7) atom to form distorted BPr4B3 pentagonal bipyramids that share  a cornercorner with one Cl(8)Pr6 octahedra, corners with two equivalent Cl(5)Pr6 octahedra,  a cornercorner with one Cl(4)Pr5 trigonal bipyramid,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one B(7)Pr4B3 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 28-65°. In the fourth B site, B(4) is bonded in a 7-coordinate geometry to one Pr(1), one Pr(2), one Pr(3), one Pr(5), one Pr(8), one B(3), and one B(7) atom. In the fifth B site, B(5) is bonded to one Pr(1), one Pr(2), one Pr(4), one Pr(5), one Pr(8), and one B(6) atom to form BPr5B octahedra that share  a cornercorner with one Cl(5)Pr6 octahedra,  a cornercorner with one Cl(8)Pr6 octahedra,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids, corners with three equivalent Cl(4)Pr5 trigonal bipyramids,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(1)Pr5 trigonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one Cl(6)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 54°. In the sixth B site, B(6) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(2), one Pr(5), one Pr(8), two equivalent Pr(6), one B(1), one B(2), and one B(5) atom. In the seventh B site, B(7) is bonded to one Pr(1), one Pr(5), two equivalent Pr(7), one B(1), one B(3), and one B(4) atom to form distorted BPr4B3 pentagonal bipyramids that share  a cornercorner with one Cl(5)Pr6 octahedra, corners with two equivalent Cl(8)Pr6 octahedra,  a cornercorner with one Cl(4)Pr5 trigonal bipyramid,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one B(3)Pr4B3 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 27-65°. There are eight inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one Pr(1), one Pr(2), one Pr(5), one Pr(6), and one Pr(8) atom to form distorted ClPr5 trigonal bipyramids that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with two equivalent Cl(4)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one Cl(6)Pr5 trigonal bipyramid, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 20°. In the second Cl site, Cl(2) is bonded to one Pr(1), one Pr(2), one Pr(5), one Pr(7), and one Pr(8) atom to form distorted ClPr5 trigonal bipyramids that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with two equivalent Cl(6)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(4)Pr5 trigonal bipyramid, and edges with two equivalent Cl(1)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 14°. In the third Cl site, Cl(3) is bonded in a distorted rectangular see-saw-like geometry to one Pr(1), one Pr(3), and two equivalent Pr(4) atoms. In the fourth Cl site, Cl(4) is bonded to one Pr(4), one Pr(5), one Pr(8), and two equivalent Pr(3) atoms to form distorted ClPr5 trigonal bipyramids that share corners with three equivalent B(5)Pr5B octahedra,  a cornercorner with one B(3)Pr4B3 pentagonal bipyramid,  a cornercorner with one B(7)Pr4B3 pentagonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid,  an edgeedge with one Cl(4)Pr5 trigonal bipyramid, and edges with three equivalent Cl(6)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. In the fifth Cl site, Cl(5) is bonded to two equivalent Pr(1), two equivalent Pr(6), and two equivalent Pr(7) atoms to form distorted ClPr6 octahedra that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with four equivalent B(3)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(8)Pr6 octahedra, edges with two equivalent B(7)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(1)Pr5 trigonal bipyramids, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 54°. In the sixth Cl site, Cl(6) is bonded to one Pr(3), one Pr(5), one Pr(8), and two equivalent Pr(4) atoms to form distorted ClPr5 trigonal bipyramids that share  a cornercorner with one B(5)Pr5B octahedra,  a cornercorner with one B(3)Pr4B3 pentagonal bipyramid,  a cornercorner with one B(7)Pr4B3 pentagonal bipyramid, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one Cl(1)Pr5 trigonal bipyramid,  an edgeedge with one Cl(6)Pr5 trigonal bipyramid, edges with three equivalent Cl(4)Pr5 trigonal bipyramids, and  a faceface with one B(5)Pr5B octahedra. The corner-sharing octahedral tilt angles are 54°. In the seventh Cl site, Cl(7) is bonded in a 3-coordinate geometry to one Pr(2), one Pr(3), and one Pr(4) atom. In the eighth Cl site, Cl(8) is bonded to two equivalent Pr(2), two equivalent Pr(6), and two equivalent Pr(7) atoms to form distorted ClPr6 octahedra that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with four equivalent B(7)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(5)Pr6 octahedra, edges with two equivalent B(3)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(1)Pr5 trigonal bipyramids, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 54°.
Pr8(BCl)7 crystallizes in the triclinic P-1 space group. There are eight inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 7-coordinate geometry to one B(1), one B(4), one B(5), one B(6), one B(7), one Cl(1), one Cl(2), one Cl(3), and one Cl(5) atom. The Pr(1)-B(1) bond length is 3.00 Å. The Pr(1)-B(4) bond length is 2.77 Å. The Pr(1)-B(5) bond length is 2.62 Å. The Pr(1)-B(6) bond length is 2.94 Å. The Pr(1)-B(7) bond length is 2.64 Å. The Pr(1)-Cl(1) bond length is 3.09 Å. The Pr(1)-Cl(2) bond length is 3.05 Å. The Pr(1)-Cl(3) bond length is 2.92 Å. The Pr(1)-Cl(5) bond length is 3.25 Å. In the second Pr site, Pr(2) is bonded in a 7-coordinate geometry to one B(2), one B(3), one B(4), one B(5), one B(6), one Cl(1), one Cl(2), one Cl(7), and one Cl(8) atom. The Pr(2)-B(2) bond length is 3.00 Å. The Pr(2)-B(3) bond length is 2.64 Å. The Pr(2)-B(4) bond length is 2.77 Å. The Pr(2)-B(5) bond length is 2.62 Å. The Pr(2)-B(6) bond length is 2.94 Å. The Pr(2)-Cl(1) bond length is 3.08 Å. The Pr(2)-Cl(2) bond length is 3.05 Å. The Pr(2)-Cl(7) bond length is 2.91 Å. The Pr(2)-Cl(8) bond length is 3.25 Å. In the third Pr site, Pr(3) is bonded in a 6-coordinate geometry to one B(4), one Cl(3), one Cl(6), one Cl(7), and two equivalent Cl(4) atoms. The Pr(3)-B(4) bond length is 2.65 Å. The Pr(3)-Cl(3) bond length is 2.89 Å. The Pr(3)-Cl(6) bond length is 3.01 Å. The Pr(3)-Cl(7) bond length is 2.89 Å. There is one shorter (3.00 Å) and one longer (3.01 Å) Pr(3)-Cl(4) bond length. In the fourth Pr site, Pr(4) is bonded in a 7-coordinate geometry to one B(5), one Cl(4), one Cl(7), two equivalent Cl(3), and two equivalent Cl(6) atoms. The Pr(4)-B(5) bond length is 2.49 Å. The Pr(4)-Cl(4) bond length is 3.01 Å. The Pr(4)-Cl(7) bond length is 2.88 Å. There is one shorter (2.88 Å) and one longer (3.36 Å) Pr(4)-Cl(3) bond length. There is one shorter (3.01 Å) and one longer (3.03 Å) Pr(4)-Cl(6) bond length. In the fifth Pr site, Pr(5) is bonded in a 7-coordinate geometry to one B(1), one B(4), one B(5), one B(6), one B(7), one Cl(1), one Cl(2), one Cl(4), and one Cl(6) atom. The Pr(5)-B(1) bond length is 2.96 Å. The Pr(5)-B(4) bond length is 2.72 Å. The Pr(5)-B(5) bond length is 2.63 Å. The Pr(5)-B(6) bond length is 2.96 Å. The Pr(5)-B(7) bond length is 2.68 Å. The Pr(5)-Cl(1) bond length is 3.12 Å. The Pr(5)-Cl(2) bond length is 3.15 Å. The Pr(5)-Cl(4) bond length is 3.23 Å. The Pr(5)-Cl(6) bond length is 3.15 Å. In the sixth Pr site, Pr(6) is bonded in a 9-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(6), one Cl(1), one Cl(5), and one Cl(8) atom. There is one shorter (2.70 Å) and one longer (2.74 Å) Pr(6)-B(1) bond length. There is one shorter (2.70 Å) and one longer (2.74 Å) Pr(6)-B(2) bond length. Both Pr(6)-B(6) bond lengths are 2.74 Å. The Pr(6)-Cl(1) bond length is 2.96 Å. The Pr(6)-Cl(5) bond length is 3.04 Å. The Pr(6)-Cl(8) bond length is 3.04 Å. In the seventh Pr site, Pr(7) is bonded in a 7-coordinate geometry to two equivalent B(1), two equivalent B(2), two equivalent B(3), two equivalent B(7), one Cl(2), one Cl(5), and one Cl(8) atom. There is one shorter (3.04 Å) and one longer (3.06 Å) Pr(7)-B(1) bond length. There is one shorter (3.03 Å) and one longer (3.07 Å) Pr(7)-B(2) bond length. There is one shorter (2.69 Å) and one longer (2.71 Å) Pr(7)-B(3) bond length. There is one shorter (2.70 Å) and one longer (2.72 Å) Pr(7)-B(7) bond length. The Pr(7)-Cl(2) bond length is 2.96 Å. The Pr(7)-Cl(5) bond length is 3.13 Å. The Pr(7)-Cl(8) bond length is 3.13 Å. In the eighth Pr site, Pr(8) is bonded in a 9-coordinate geometry to one B(2), one B(3), one B(4), one B(5), one B(6), one Cl(1), one Cl(2), one Cl(4), and one Cl(6) atom. The Pr(8)-B(2) bond length is 2.95 Å. The Pr(8)-B(3) bond length is 2.67 Å. The Pr(8)-B(4) bond length is 2.72 Å. The Pr(8)-B(5) bond length is 2.63 Å. The Pr(8)-B(6) bond length is 2.95 Å. The Pr(8)-Cl(1) bond length is 3.11 Å. The Pr(8)-Cl(2) bond length is 3.15 Å. The Pr(8)-Cl(4) bond length is 3.31 Å. The Pr(8)-Cl(6) bond length is 3.19 Å. There are seven inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(5), two equivalent Pr(6), two equivalent Pr(7), one B(2), one B(6), and one B(7) atom. The B(1)-B(2) bond length is 1.97 Å. The B(1)-B(6) bond length is 1.89 Å. The B(1)-B(7) bond length is 1.68 Å. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Pr(2), one Pr(8), two equivalent Pr(6), two equivalent Pr(7), one B(1), one B(3), and one B(6) atom. The B(2)-B(3) bond length is 1.68 Å. The B(2)-B(6) bond length is 1.89 Å. In the third B site, B(3) is bonded to one Pr(2), one Pr(8), two equivalent Pr(7), one B(2), one B(4), and one B(7) atom to form distorted BPr4B3 pentagonal bipyramids that share  a cornercorner with one Cl(8)Pr6 octahedra, corners with two equivalent Cl(5)Pr6 octahedra,  a cornercorner with one Cl(4)Pr5 trigonal bipyramid,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one B(7)Pr4B3 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 28-65°. The B(3)-B(4) bond length is 1.74 Å. The B(3)-B(7) bond length is 1.63 Å. In the fourth B site, B(4) is bonded in a 7-coordinate geometry to one Pr(1), one Pr(2), one Pr(3), one Pr(5), one Pr(8), one B(3), and one B(7) atom. The B(4)-B(7) bond length is 1.74 Å. In the fifth B site, B(5) is bonded to one Pr(1), one Pr(2), one Pr(4), one Pr(5), one Pr(8), and one B(6) atom to form BPr5B octahedra that share  a cornercorner with one Cl(5)Pr6 octahedra,  a cornercorner with one Cl(8)Pr6 octahedra,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids, corners with three equivalent Cl(4)Pr5 trigonal bipyramids,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(1)Pr5 trigonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one Cl(6)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 54°. The B(5)-B(6) bond length is 1.74 Å. In the sixth B site, B(6) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(2), one Pr(5), one Pr(8), two equivalent Pr(6), one B(1), one B(2), and one B(5) atom. In the seventh B site, B(7) is bonded to one Pr(1), one Pr(5), two equivalent Pr(7), one B(1), one B(3), and one B(4) atom to form distorted BPr4B3 pentagonal bipyramids that share  a cornercorner with one Cl(5)Pr6 octahedra, corners with two equivalent Cl(8)Pr6 octahedra,  a cornercorner with one Cl(4)Pr5 trigonal bipyramid,  a cornercorner with one Cl(6)Pr5 trigonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid, and  a faceface with one B(3)Pr4B3 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 27-65°. There are eight inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one Pr(1), one Pr(2), one Pr(5), one Pr(6), and one Pr(8) atom to form distorted ClPr5 trigonal bipyramids that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with two equivalent Cl(4)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one Cl(6)Pr5 trigonal bipyramid, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 20°. In the second Cl site, Cl(2) is bonded to one Pr(1), one Pr(2), one Pr(5), one Pr(7), and one Pr(8) atom to form distorted ClPr5 trigonal bipyramids that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with two equivalent Cl(6)Pr5 trigonal bipyramids,  an edgeedge with one B(5)Pr5B octahedra,  an edgeedge with one Cl(5)Pr6 octahedra,  an edgeedge with one Cl(8)Pr6 octahedra,  an edgeedge with one B(3)Pr4B3 pentagonal bipyramid,  an edgeedge with one B(7)Pr4B3 pentagonal bipyramid,  an edgeedge with one Cl(4)Pr5 trigonal bipyramid, and edges with two equivalent Cl(1)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 14°. In the third Cl site, Cl(3) is bonded in a distorted rectangular see-saw-like geometry to one Pr(1), one Pr(3), and two equivalent Pr(4) atoms. In the fourth Cl site, Cl(4) is bonded to one Pr(4), one Pr(5), one Pr(8), and two equivalent Pr(3) atoms to form distorted ClPr5 trigonal bipyramids that share corners with three equivalent B(5)Pr5B octahedra,  a cornercorner with one B(3)Pr4B3 pentagonal bipyramid,  a cornercorner with one B(7)Pr4B3 pentagonal bipyramid, corners with two equivalent Cl(1)Pr5 trigonal bipyramids,  an edgeedge with one Cl(2)Pr5 trigonal bipyramid,  an edgeedge with one Cl(4)Pr5 trigonal bipyramid, and edges with three equivalent Cl(6)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. In the fifth Cl site, Cl(5) is bonded to two equivalent Pr(1), two equivalent Pr(6), and two equivalent Pr(7) atoms to form distorted ClPr6 octahedra that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(7)Pr4B3 pentagonal bipyramids, corners with four equivalent B(3)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(8)Pr6 octahedra, edges with two equivalent B(7)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(1)Pr5 trigonal bipyramids, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 54°. In the sixth Cl site, Cl(6) is bonded to one Pr(3), one Pr(5), one Pr(8), and two equivalent Pr(4) atoms to form distorted ClPr5 trigonal bipyramids that share  a cornercorner with one B(5)Pr5B octahedra,  a cornercorner with one B(3)Pr4B3 pentagonal bipyramid,  a cornercorner with one B(7)Pr4B3 pentagonal bipyramid, corners with two equivalent Cl(2)Pr5 trigonal bipyramids,  an edgeedge with one Cl(1)Pr5 trigonal bipyramid,  an edgeedge with one Cl(6)Pr5 trigonal bipyramid, edges with three equivalent Cl(4)Pr5 trigonal bipyramids, and  a faceface with one B(5)Pr5B octahedra. The corner-sharing octahedral tilt angles are 54°. In the seventh Cl site, Cl(7) is bonded in a 3-coordinate geometry to one Pr(2), one Pr(3), and one Pr(4) atom. In the eighth Cl site, Cl(8) is bonded to two equivalent Pr(2), two equivalent Pr(6), and two equivalent Pr(7) atoms to form distorted ClPr6 octahedra that share corners with two equivalent B(5)Pr5B octahedra, corners with two equivalent B(3)Pr4B3 pentagonal bipyramids, corners with four equivalent B(7)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(5)Pr6 octahedra, edges with two equivalent B(3)Pr4B3 pentagonal bipyramids, edges with two equivalent Cl(1)Pr5 trigonal bipyramids, and edges with two equivalent Cl(2)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 54°.