Nd6Al7Si5N3O25 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are six inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to one N(2), one N(3), one O(21), one O(23), one O(3), one O(4), one O(6), and one O(9) atom. In the second Nd site, Nd(2) is bonded in a 8-coordinate geometry to one N(1), one O(20), one O(22), one O(24), one O(25), one O(5), one O(7), and one O(8) atom. In the third Nd site, Nd(3) is bonded in a 7-coordinate geometry to one N(2), one O(14), one O(16), one O(19), one O(21), one O(6), and one O(9) atom. In the fourth Nd site, Nd(4) is bonded in a 8-coordinate geometry to one O(10), one O(15), one O(17), one O(18), one O(20), one O(22), one O(7), and one O(8) atom. In the fifth Nd site, Nd(5) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(13), one O(14), one O(21), one O(23), one O(3), and one O(6) atom. In the sixth Nd site, Nd(6) is bonded in a 8-coordinate geometry to one N(1), one O(10), one O(12), one O(15), one O(2), one O(20), one O(24), and one O(7) atom. There are seven inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(19), one O(2), one O(22), and one O(3) atom to form AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 58-62°. In the second Al site, Al(2) is bonded to one N(3), one O(1), one O(13), one O(16), one O(19), and one O(4) atom to form AlNO5 octahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra,  a cornercorner with one Si(5)N2O2 tetrahedra, and  an edgeedge with one Al(5)NO4 trigonal bipyramid. In the third Al site, Al(3) is bonded to one O(12), one O(17), one O(18), one O(2), one O(25), and one O(5) atom to form AlO6 octahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra,  a cornercorner with one Si(5)N2O2 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. In the fourth Al site, Al(4) is bonded to one O(12), one O(14), one O(4), and one O(8) atom to form distorted AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 61-66°. In the fifth Al site, Al(5) is bonded to one N(3), one O(13), one O(15), one O(5), and one O(9) atom to form AlNO4 trigonal bipyramids that share  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  an edgeedge with one Al(2)NO5 octahedra. The corner-sharing octahedral tilt angles are 61°. In the sixth Al site, Al(6) is bonded to one O(10), one O(16), one O(23), and one O(25) atom to form distorted AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 62-65°. In the seventh Al site, Al(7) is bonded to one N(3), one O(11), one O(17), and one O(24) atom to form AlNO3 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 66-68°. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one O(10), one O(6), and one O(8) atom to form SiNO3 tetrahedra that share  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra, and  a cornercorner with one Si(5)N2O2 tetrahedra. In the second Si site, Si(2) is bonded to one O(11), one O(3), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. In the third Si site, Si(3) is bonded to one O(15), one O(21), one O(22), and one O(24) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. In the fourth Si site, Si(4) is bonded to one N(2), one O(14), one O(20), and one O(23) atom to form SiNO3 tetrahedra that share  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra, and  a cornercorner with one Si(5)N2O2 tetrahedra. In the fifth Si site, Si(5) is bonded to one N(1), one N(2), one O(1), and one O(18) atom to form SiN2O2 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 56-57°. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to one Nd(2), one Nd(6), one Si(1), and one Si(5) atom. In the second N site, N(2) is bonded to one Nd(1), one Nd(3), one Si(4), and one Si(5) atom to form distorted NNd2Si2 tetrahedra that share  a cornercorner with one N(3)NdAl3 tetrahedra,  a cornercorner with one O(20)Nd3Si tetrahedra, and corners with two equivalent O(6)Nd3Si tetrahedra. In the third N site, N(3) is bonded to one Nd(1), one Al(2), one Al(5), and one Al(7) atom to form distorted NNdAl3 tetrahedra that share  a cornercorner with one N(2)Nd2Si2 tetrahedra and  a cornercorner with one O(6)Nd3Si tetrahedra. There are twenty-five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Nd(5), one Al(2), and one Si(5) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nd(6), one Al(1), and one Al(3) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Nd(1), one Nd(5), one Al(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Nd(1), one Al(2), and one Al(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nd(2), one Al(3), and one Al(5) atom. In the sixth O site, O(6) is bonded to one Nd(1), one Nd(3), one Nd(5), and one Si(1) atom to form distorted ONd3Si tetrahedra that share  a cornercorner with one N(3)NdAl3 tetrahedra and corners with two equivalent N(2)Nd2Si2 tetrahedra. In the seventh O site, O(7) is bonded to one Nd(2), one Nd(4), one Nd(6), and one Si(2) atom to form distorted corner-sharing ONd3Si tetrahedra. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Nd(2), one Nd(4), one Al(4), and one Si(1) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Nd(1), one Nd(3), one Al(5), and one Si(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Nd(4), one Nd(6), one Al(6), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nd(5), one Al(7), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Nd(6), one Al(3), and one Al(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Nd(5), one Al(2), and one Al(5) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Nd(3), one Nd(5), one Al(4), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Nd(4), one Nd(6), one Al(5), and one Si(3) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Nd(3), one Al(2), and one Al(6) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Nd(4), one Al(3), and one Al(7) atom. In the eighteenth O site, O(18) is bonded in a 3-coordinate geometry to one Nd(4), one Al(3), and one Si(5) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Nd(3), one Al(1), and one Al(2) atom. In the twentieth O site, O(20) is bonded to one Nd(2), one Nd(4), one Nd(6), and one Si(4) atom to form distorted ONd3Si tetrahedra that share  a cornercorner with one N(2)Nd2Si2 tetrahedra and corners with three equivalent O(7)Nd3Si tetrahedra. In the twenty-first O site, O(21) is bonded in a distorted single-bond geometry to one Nd(1), one Nd(3), one Nd(5), and one Si(3) atom. In the twenty-second O site, O(22) is bonded in a 2-coordinate geometry to one Nd(2), one Nd(4), one Al(1), and one Si(3) atom. In the twenty-third O site, O(23) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(5), one Al(6), and one Si(4) atom. In the twenty-fourth O site, O(24) is bonded in a 4-coordinate geometry to one Nd(2), one Nd(6), one Al(7), and one Si(3) atom. In the twenty-fifth O site, O(25) is bonded in a 3-coordinate geometry to one Nd(2), one Al(3), and one Al(6) atom.
Nd6Al7Si5N3O25 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. There are six inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to one N(2), one N(3), one O(21), one O(23), one O(3), one O(4), one O(6), and one O(9) atom. The Nd(1)-N(2) bond length is 2.59 Å. The Nd(1)-N(3) bond length is 2.32 Å. The Nd(1)-O(21) bond length is 2.66 Å. The Nd(1)-O(23) bond length is 2.82 Å. The Nd(1)-O(3) bond length is 2.54 Å. The Nd(1)-O(4) bond length is 2.31 Å. The Nd(1)-O(6) bond length is 2.68 Å. The Nd(1)-O(9) bond length is 2.82 Å. In the second Nd site, Nd(2) is bonded in a 8-coordinate geometry to one N(1), one O(20), one O(22), one O(24), one O(25), one O(5), one O(7), and one O(8) atom. The Nd(2)-N(1) bond length is 2.52 Å. The Nd(2)-O(20) bond length is 2.67 Å. The Nd(2)-O(22) bond length is 2.54 Å. The Nd(2)-O(24) bond length is 2.79 Å. The Nd(2)-O(25) bond length is 2.30 Å. The Nd(2)-O(5) bond length is 2.28 Å. The Nd(2)-O(7) bond length is 2.68 Å. The Nd(2)-O(8) bond length is 2.86 Å. In the third Nd site, Nd(3) is bonded in a 7-coordinate geometry to one N(2), one O(14), one O(16), one O(19), one O(21), one O(6), and one O(9) atom. The Nd(3)-N(2) bond length is 2.61 Å. The Nd(3)-O(14) bond length is 2.55 Å. The Nd(3)-O(16) bond length is 2.26 Å. The Nd(3)-O(19) bond length is 2.27 Å. The Nd(3)-O(21) bond length is 2.68 Å. The Nd(3)-O(6) bond length is 2.65 Å. The Nd(3)-O(9) bond length is 2.55 Å. In the fourth Nd site, Nd(4) is bonded in a 8-coordinate geometry to one O(10), one O(15), one O(17), one O(18), one O(20), one O(22), one O(7), and one O(8) atom. The Nd(4)-O(10) bond length is 2.80 Å. The Nd(4)-O(15) bond length is 2.52 Å. The Nd(4)-O(17) bond length is 2.30 Å. The Nd(4)-O(18) bond length is 2.43 Å. The Nd(4)-O(20) bond length is 2.61 Å. The Nd(4)-O(22) bond length is 2.82 Å. The Nd(4)-O(7) bond length is 2.59 Å. The Nd(4)-O(8) bond length is 2.51 Å. In the fifth Nd site, Nd(5) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(13), one O(14), one O(21), one O(23), one O(3), and one O(6) atom. The Nd(5)-O(1) bond length is 2.39 Å. The Nd(5)-O(11) bond length is 2.53 Å. The Nd(5)-O(13) bond length is 2.23 Å. The Nd(5)-O(14) bond length is 2.69 Å. The Nd(5)-O(21) bond length is 2.62 Å. The Nd(5)-O(23) bond length is 2.51 Å. The Nd(5)-O(3) bond length is 2.90 Å. The Nd(5)-O(6) bond length is 2.62 Å. In the sixth Nd site, Nd(6) is bonded in a 8-coordinate geometry to one N(1), one O(10), one O(12), one O(15), one O(2), one O(20), one O(24), and one O(7) atom. The Nd(6)-N(1) bond length is 2.68 Å. The Nd(6)-O(10) bond length is 2.56 Å. The Nd(6)-O(12) bond length is 2.24 Å. The Nd(6)-O(15) bond length is 2.99 Å. The Nd(6)-O(2) bond length is 2.29 Å. The Nd(6)-O(20) bond length is 2.65 Å. The Nd(6)-O(24) bond length is 2.54 Å. The Nd(6)-O(7) bond length is 2.68 Å. There are seven inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(19), one O(2), one O(22), and one O(3) atom to form AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 58-62°. The Al(1)-O(19) bond length is 1.74 Å. The Al(1)-O(2) bond length is 1.74 Å. The Al(1)-O(22) bond length is 1.84 Å. The Al(1)-O(3) bond length is 1.83 Å. In the second Al site, Al(2) is bonded to one N(3), one O(1), one O(13), one O(16), one O(19), and one O(4) atom to form AlNO5 octahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra,  a cornercorner with one Si(5)N2O2 tetrahedra, and  an edgeedge with one Al(5)NO4 trigonal bipyramid. The Al(2)-N(3) bond length is 1.96 Å. The Al(2)-O(1) bond length is 2.08 Å. The Al(2)-O(13) bond length is 1.95 Å. The Al(2)-O(16) bond length is 1.89 Å. The Al(2)-O(19) bond length is 1.96 Å. The Al(2)-O(4) bond length is 1.96 Å. In the third Al site, Al(3) is bonded to one O(12), one O(17), one O(18), one O(2), one O(25), and one O(5) atom to form AlO6 octahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra,  a cornercorner with one Si(5)N2O2 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. The Al(3)-O(12) bond length is 1.88 Å. The Al(3)-O(17) bond length is 1.92 Å. The Al(3)-O(18) bond length is 2.03 Å. The Al(3)-O(2) bond length is 1.94 Å. The Al(3)-O(25) bond length is 1.94 Å. The Al(3)-O(5) bond length is 1.90 Å. In the fourth Al site, Al(4) is bonded to one O(12), one O(14), one O(4), and one O(8) atom to form distorted AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 61-66°. The Al(4)-O(12) bond length is 1.74 Å. The Al(4)-O(14) bond length is 1.84 Å. The Al(4)-O(4) bond length is 1.75 Å. The Al(4)-O(8) bond length is 1.85 Å. In the fifth Al site, Al(5) is bonded to one N(3), one O(13), one O(15), one O(5), and one O(9) atom to form AlNO4 trigonal bipyramids that share  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  an edgeedge with one Al(2)NO5 octahedra. The corner-sharing octahedral tilt angles are 61°. The Al(5)-N(3) bond length is 1.98 Å. The Al(5)-O(13) bond length is 1.82 Å. The Al(5)-O(15) bond length is 2.09 Å. The Al(5)-O(5) bond length is 1.80 Å. The Al(5)-O(9) bond length is 1.88 Å. In the sixth Al site, Al(6) is bonded to one O(10), one O(16), one O(23), and one O(25) atom to form distorted AlO4 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 62-65°. The Al(6)-O(10) bond length is 1.84 Å. The Al(6)-O(16) bond length is 1.75 Å. The Al(6)-O(23) bond length is 1.84 Å. The Al(6)-O(25) bond length is 1.76 Å. In the seventh Al site, Al(7) is bonded to one N(3), one O(11), one O(17), and one O(24) atom to form AlNO3 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 66-68°. The Al(7)-N(3) bond length is 1.80 Å. The Al(7)-O(11) bond length is 1.85 Å. The Al(7)-O(17) bond length is 1.78 Å. The Al(7)-O(24) bond length is 1.86 Å. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one O(10), one O(6), and one O(8) atom to form SiNO3 tetrahedra that share  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra, and  a cornercorner with one Si(5)N2O2 tetrahedra. The Si(1)-N(1) bond length is 1.69 Å. The Si(1)-O(10) bond length is 1.67 Å. The Si(1)-O(6) bond length is 1.64 Å. The Si(1)-O(8) bond length is 1.67 Å. In the second Si site, Si(2) is bonded to one O(11), one O(3), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. The Si(2)-O(11) bond length is 1.65 Å. The Si(2)-O(3) bond length is 1.65 Å. The Si(2)-O(7) bond length is 1.63 Å. The Si(2)-O(9) bond length is 1.64 Å. In the third Si site, Si(3) is bonded to one O(15), one O(21), one O(22), and one O(24) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(7)NO3 tetrahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(5)NO4 trigonal bipyramid. The Si(3)-O(15) bond length is 1.64 Å. The Si(3)-O(21) bond length is 1.63 Å. The Si(3)-O(22) bond length is 1.67 Å. The Si(3)-O(24) bond length is 1.66 Å. In the fourth Si site, Si(4) is bonded to one N(2), one O(14), one O(20), and one O(23) atom to form SiNO3 tetrahedra that share  a cornercorner with one Al(4)O4 tetrahedra,  a cornercorner with one Al(6)O4 tetrahedra, and  a cornercorner with one Si(5)N2O2 tetrahedra. The Si(4)-N(2) bond length is 1.68 Å. The Si(4)-O(14) bond length is 1.68 Å. The Si(4)-O(20) bond length is 1.64 Å. The Si(4)-O(23) bond length is 1.67 Å. In the fifth Si site, Si(5) is bonded to one N(1), one N(2), one O(1), and one O(18) atom to form SiN2O2 tetrahedra that share  a cornercorner with one Al(2)NO5 octahedra,  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Si(1)NO3 tetrahedra, and  a cornercorner with one Si(4)NO3 tetrahedra. The corner-sharing octahedral tilt angles range from 56-57°. The Si(5)-N(1) bond length is 1.74 Å. The Si(5)-N(2) bond length is 1.73 Å. The Si(5)-O(1) bond length is 1.68 Å. The Si(5)-O(18) bond length is 1.68 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to one Nd(2), one Nd(6), one Si(1), and one Si(5) atom. In the second N site, N(2) is bonded to one Nd(1), one Nd(3), one Si(4), and one Si(5) atom to form distorted NNd2Si2 tetrahedra that share  a cornercorner with one N(3)NdAl3 tetrahedra,  a cornercorner with one O(20)Nd3Si tetrahedra, and corners with two equivalent O(6)Nd3Si tetrahedra. In the third N site, N(3) is bonded to one Nd(1), one Al(2), one Al(5), and one Al(7) atom to form distorted NNdAl3 tetrahedra that share  a cornercorner with one N(2)Nd2Si2 tetrahedra and  a cornercorner with one O(6)Nd3Si tetrahedra. There are twenty-five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Nd(5), one Al(2), and one Si(5) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nd(6), one Al(1), and one Al(3) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Nd(1), one Nd(5), one Al(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Nd(1), one Al(2), and one Al(4) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nd(2), one Al(3), and one Al(5) atom. In the sixth O site, O(6) is bonded to one Nd(1), one Nd(3), one Nd(5), and one Si(1) atom to form distorted ONd3Si tetrahedra that share  a cornercorner with one N(3)NdAl3 tetrahedra and corners with two equivalent N(2)Nd2Si2 tetrahedra. In the seventh O site, O(7) is bonded to one Nd(2), one Nd(4), one Nd(6), and one Si(2) atom to form distorted corner-sharing ONd3Si tetrahedra. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Nd(2), one Nd(4), one Al(4), and one Si(1) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Nd(1), one Nd(3), one Al(5), and one Si(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Nd(4), one Nd(6), one Al(6), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Nd(5), one Al(7), and one Si(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Nd(6), one Al(3), and one Al(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Nd(5), one Al(2), and one Al(5) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Nd(3), one Nd(5), one Al(4), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a 3-coordinate geometry to one Nd(4), one Nd(6), one Al(5), and one Si(3) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal planar geometry to one Nd(3), one Al(2), and one Al(6) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal planar geometry to one Nd(4), one Al(3), and one Al(7) atom. In the eighteenth O site, O(18) is bonded in a 3-coordinate geometry to one Nd(4), one Al(3), and one Si(5) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Nd(3), one Al(1), and one Al(2) atom. In the twentieth O site, O(20) is bonded to one Nd(2), one Nd(4), one Nd(6), and one Si(4) atom to form distorted ONd3Si tetrahedra that share  a cornercorner with one N(2)Nd2Si2 tetrahedra and corners with three equivalent O(7)Nd3Si tetrahedra. In the twenty-first O site, O(21) is bonded in a distorted single-bond geometry to one Nd(1), one Nd(3), one Nd(5), and one Si(3) atom. In the twenty-second O site, O(22) is bonded in a 2-coordinate geometry to one Nd(2), one Nd(4), one Al(1), and one Si(3) atom. In the twenty-third O site, O(23) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(5), one Al(6), and one Si(4) atom. In the twenty-fourth O site, O(24) is bonded in a 4-coordinate geometry to one Nd(2), one Nd(6), one Al(7), and one Si(3) atom. In the twenty-fifth O site, O(25) is bonded in a 3-coordinate geometry to one Nd(2), one Al(3), and one Al(6) atom.