Nd4Br9 crystallizes in the monoclinic Pc space group. There are eight inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to one Br(1), one Br(11), one Br(14), one Br(15), one Br(16), one Br(17), and one Br(2) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. In the second Nd site, Nd(2) is bonded to one Br(1), one Br(11), one Br(12), one Br(14), one Br(15), one Br(17), and one Br(2) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. In the third Nd site, Nd(3) is bonded in a 8-coordinate geometry to one Br(11), one Br(13), one Br(14), one Br(2), one Br(4), one Br(5), one Br(8), and one Br(9) atom. In the fourth Nd site, Nd(4) is bonded to one Br(10), one Br(12), one Br(16), one Br(17), one Br(18), one Br(3), and one Br(6) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. In the fifth Nd site, Nd(5) is bonded to one Br(1), one Br(10), one Br(12), one Br(16), one Br(18), one Br(3), and one Br(6) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. In the sixth Nd site, Nd(6) is bonded in a 8-coordinate geometry to one Br(11), one Br(13), one Br(15), one Br(2), one Br(4), one Br(5), one Br(7), and one Br(8) atom. In the seventh Nd site, Nd(7) is bonded in a 8-coordinate geometry to one Br(13), one Br(18), one Br(3), one Br(4), one Br(5), one Br(6), one Br(7), and one Br(9) atom. In the eighth Nd site, Nd(8) is bonded in a 8-coordinate geometry to one Br(10), one Br(18), one Br(4), one Br(5), one Br(6), one Br(7), one Br(8), and one Br(9) atom. There are eighteen inequivalent Br sites. In the first Br site, Br(1) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(5) atom. In the second Br site, Br(2) is bonded to one Nd(1), one Nd(2), one Nd(3), and one Nd(6) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the third Br site, Br(3) is bonded in a distorted trigonal planar geometry to one Nd(4), one Nd(5), and one Nd(7) atom. In the fourth Br site, Br(4) is bonded to one Nd(3), one Nd(6), one Nd(7), and one Nd(8) atom to form a mixture of corner and edge-sharing BrNd4 trigonal pyramids. In the fifth Br site, Br(5) is bonded to one Nd(3), one Nd(6), one Nd(7), and one Nd(8) atom to form a mixture of corner and edge-sharing BrNd4 trigonal pyramids. In the sixth Br site, Br(6) is bonded to one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the seventh Br site, Br(7) is bonded in a distorted trigonal non-coplanar geometry to one Nd(6), one Nd(7), and one Nd(8) atom. In the eighth Br site, Br(8) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(6), and one Nd(8) atom. In the ninth Br site, Br(9) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(7), and one Nd(8) atom. In the tenth Br site, Br(10) is bonded in a distorted trigonal planar geometry to one Nd(4), one Nd(5), and one Nd(8) atom. In the eleventh Br site, Br(11) is bonded to one Nd(1), one Nd(2), one Nd(3), and one Nd(6) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the twelfth Br site, Br(12) is bonded in a trigonal non-coplanar geometry to one Nd(2), one Nd(4), and one Nd(5) atom. In the thirteenth Br site, Br(13) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(6), and one Nd(7) atom. In the fourteenth Br site, Br(14) is bonded in a distorted trigonal planar geometry to one Nd(1), one Nd(2), and one Nd(3) atom. In the fifteenth Br site, Br(15) is bonded in a distorted trigonal planar geometry to one Nd(1), one Nd(2), and one Nd(6) atom. In the sixteenth Br site, Br(16) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(4), and one Nd(5) atom. In the seventeenth Br site, Br(17) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(4) atom. In the eighteenth Br site, Br(18) is bonded to one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids.
Nd4Br9 crystallizes in the monoclinic Pc space group. There are eight inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to one Br(1), one Br(11), one Br(14), one Br(15), one Br(16), one Br(17), and one Br(2) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. The Nd(1)-Br(1) bond length is 3.03 Å. The Nd(1)-Br(11) bond length is 3.16 Å. The Nd(1)-Br(14) bond length is 3.06 Å. The Nd(1)-Br(15) bond length is 2.99 Å. The Nd(1)-Br(16) bond length is 3.06 Å. The Nd(1)-Br(17) bond length is 3.06 Å. The Nd(1)-Br(2) bond length is 3.04 Å. In the second Nd site, Nd(2) is bonded to one Br(1), one Br(11), one Br(12), one Br(14), one Br(15), one Br(17), and one Br(2) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. The Nd(2)-Br(1) bond length is 3.04 Å. The Nd(2)-Br(11) bond length is 3.06 Å. The Nd(2)-Br(12) bond length is 3.04 Å. The Nd(2)-Br(14) bond length is 3.00 Å. The Nd(2)-Br(15) bond length is 3.04 Å. The Nd(2)-Br(17) bond length is 3.03 Å. The Nd(2)-Br(2) bond length is 3.16 Å. In the third Nd site, Nd(3) is bonded in a 8-coordinate geometry to one Br(11), one Br(13), one Br(14), one Br(2), one Br(4), one Br(5), one Br(8), and one Br(9) atom. The Nd(3)-Br(11) bond length is 3.18 Å. The Nd(3)-Br(13) bond length is 3.05 Å. The Nd(3)-Br(14) bond length is 3.04 Å. The Nd(3)-Br(2) bond length is 3.33 Å. The Nd(3)-Br(4) bond length is 3.09 Å. The Nd(3)-Br(5) bond length is 3.08 Å. The Nd(3)-Br(8) bond length is 2.96 Å. The Nd(3)-Br(9) bond length is 3.20 Å. In the fourth Nd site, Nd(4) is bonded to one Br(10), one Br(12), one Br(16), one Br(17), one Br(18), one Br(3), and one Br(6) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. The Nd(4)-Br(10) bond length is 3.08 Å. The Nd(4)-Br(12) bond length is 3.04 Å. The Nd(4)-Br(16) bond length is 3.06 Å. The Nd(4)-Br(17) bond length is 3.05 Å. The Nd(4)-Br(18) bond length is 3.04 Å. The Nd(4)-Br(3) bond length is 3.00 Å. The Nd(4)-Br(6) bond length is 3.13 Å. In the fifth Nd site, Nd(5) is bonded to one Br(1), one Br(10), one Br(12), one Br(16), one Br(18), one Br(3), and one Br(6) atom to form a mixture of distorted corner and edge-sharing NdBr7 pentagonal bipyramids. The Nd(5)-Br(1) bond length is 3.03 Å. The Nd(5)-Br(10) bond length is 2.99 Å. The Nd(5)-Br(12) bond length is 3.04 Å. The Nd(5)-Br(16) bond length is 3.04 Å. The Nd(5)-Br(18) bond length is 3.15 Å. The Nd(5)-Br(3) bond length is 3.05 Å. The Nd(5)-Br(6) bond length is 3.06 Å. In the sixth Nd site, Nd(6) is bonded in a 8-coordinate geometry to one Br(11), one Br(13), one Br(15), one Br(2), one Br(4), one Br(5), one Br(7), and one Br(8) atom. The Nd(6)-Br(11) bond length is 3.34 Å. The Nd(6)-Br(13) bond length is 2.95 Å. The Nd(6)-Br(15) bond length is 3.02 Å. The Nd(6)-Br(2) bond length is 3.16 Å. The Nd(6)-Br(4) bond length is 3.08 Å. The Nd(6)-Br(5) bond length is 3.13 Å. The Nd(6)-Br(7) bond length is 3.18 Å. The Nd(6)-Br(8) bond length is 3.03 Å. In the seventh Nd site, Nd(7) is bonded in a 8-coordinate geometry to one Br(13), one Br(18), one Br(3), one Br(4), one Br(5), one Br(6), one Br(7), and one Br(9) atom. The Nd(7)-Br(13) bond length is 3.17 Å. The Nd(7)-Br(18) bond length is 3.20 Å. The Nd(7)-Br(3) bond length is 3.03 Å. The Nd(7)-Br(4) bond length is 3.07 Å. The Nd(7)-Br(5) bond length is 3.11 Å. The Nd(7)-Br(6) bond length is 3.31 Å. The Nd(7)-Br(7) bond length is 2.96 Å. The Nd(7)-Br(9) bond length is 3.06 Å. In the eighth Nd site, Nd(8) is bonded in a 8-coordinate geometry to one Br(10), one Br(18), one Br(4), one Br(5), one Br(6), one Br(7), one Br(8), and one Br(9) atom. The Nd(8)-Br(10) bond length is 3.03 Å. The Nd(8)-Br(18) bond length is 3.30 Å. The Nd(8)-Br(4) bond length is 3.12 Å. The Nd(8)-Br(5) bond length is 3.09 Å. The Nd(8)-Br(6) bond length is 3.15 Å. The Nd(8)-Br(7) bond length is 3.02 Å. The Nd(8)-Br(8) bond length is 3.20 Å. The Nd(8)-Br(9) bond length is 2.96 Å. There are eighteen inequivalent Br sites. In the first Br site, Br(1) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(5) atom. In the second Br site, Br(2) is bonded to one Nd(1), one Nd(2), one Nd(3), and one Nd(6) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the third Br site, Br(3) is bonded in a distorted trigonal planar geometry to one Nd(4), one Nd(5), and one Nd(7) atom. In the fourth Br site, Br(4) is bonded to one Nd(3), one Nd(6), one Nd(7), and one Nd(8) atom to form a mixture of corner and edge-sharing BrNd4 trigonal pyramids. In the fifth Br site, Br(5) is bonded to one Nd(3), one Nd(6), one Nd(7), and one Nd(8) atom to form a mixture of corner and edge-sharing BrNd4 trigonal pyramids. In the sixth Br site, Br(6) is bonded to one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the seventh Br site, Br(7) is bonded in a distorted trigonal non-coplanar geometry to one Nd(6), one Nd(7), and one Nd(8) atom. In the eighth Br site, Br(8) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(6), and one Nd(8) atom. In the ninth Br site, Br(9) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(7), and one Nd(8) atom. In the tenth Br site, Br(10) is bonded in a distorted trigonal planar geometry to one Nd(4), one Nd(5), and one Nd(8) atom. In the eleventh Br site, Br(11) is bonded to one Nd(1), one Nd(2), one Nd(3), and one Nd(6) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids. In the twelfth Br site, Br(12) is bonded in a trigonal non-coplanar geometry to one Nd(2), one Nd(4), and one Nd(5) atom. In the thirteenth Br site, Br(13) is bonded in a distorted trigonal non-coplanar geometry to one Nd(3), one Nd(6), and one Nd(7) atom. In the fourteenth Br site, Br(14) is bonded in a distorted trigonal planar geometry to one Nd(1), one Nd(2), and one Nd(3) atom. In the fifteenth Br site, Br(15) is bonded in a distorted trigonal planar geometry to one Nd(1), one Nd(2), and one Nd(6) atom. In the sixteenth Br site, Br(16) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(4), and one Nd(5) atom. In the seventeenth Br site, Br(17) is bonded in a trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(4) atom. In the eighteenth Br site, Br(18) is bonded to one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom to form a mixture of distorted corner and edge-sharing BrNd4 trigonal pyramids.