K2(NbBr3)3 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one Br(12), one Br(14), one Br(15), one Br(17), one Br(18), and one Br(2) atom. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Br(1), one Br(11), one Br(14), one Br(16), one Br(17), and one Br(18) atom. In the third K site, K(3) is bonded in a 6-coordinate geometry to one Br(1), one Br(10), one Br(13), one Br(16), one Br(17), and one Br(2) atom. In the fourth K site, K(4) is bonded in a 6-coordinate geometry to one Br(1), one Br(13), one Br(15), one Br(18), one Br(2), and one Br(9) atom. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Br(14), one Br(2), one Br(4), one Br(6), and one Br(9) atom to form distorted corner-sharing NbBr5 square pyramids. In the second Nb site, Nb(2) is bonded to one Br(1), one Br(10), one Br(14), one Br(3), and one Br(5) atom to form distorted corner-sharing NbBr5 square pyramids. In the third Nb site, Nb(3) is bonded to one Br(11), one Br(13), one Br(17), one Br(3), and one Br(8) atom to form distorted corner-sharing NbBr5 square pyramids. In the fourth Nb site, Nb(4) is bonded to one Br(12), one Br(13), one Br(18), one Br(4), and one Br(7) atom to form distorted corner-sharing NbBr5 square pyramids. In the fifth Nb site, Nb(5) is bonded to one Br(10), one Br(11), one Br(15), one Br(6), and one Br(7) atom to form distorted corner-sharing NbBr5 square pyramids. In the sixth Nb site, Nb(6) is bonded to one Br(12), one Br(16), one Br(5), one Br(8), and one Br(9) atom to form distorted corner-sharing NbBr5 square pyramids. There are eighteen inequivalent Br sites. In the first Br site, Br(1) is bonded to one K(2), one K(3), one K(4), and one Nb(2) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the second Br site, Br(2) is bonded to one K(1), one K(3), one K(4), and one Nb(1) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the third Br site, Br(3) is bonded in a 2-coordinate geometry to one Nb(2) and one Nb(3) atom. In the fourth Br site, Br(4) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(4) atom. In the fifth Br site, Br(5) is bonded in a 2-coordinate geometry to one Nb(2) and one Nb(6) atom. In the sixth Br site, Br(6) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(5) atom. In the seventh Br site, Br(7) is bonded in a 2-coordinate geometry to one Nb(4) and one Nb(5) atom. In the eighth Br site, Br(8) is bonded in a 2-coordinate geometry to one Nb(3) and one Nb(6) atom. In the ninth Br site, Br(9) is bonded in a 3-coordinate geometry to one K(4), one Nb(1), and one Nb(6) atom. In the tenth Br site, Br(10) is bonded in a 3-coordinate geometry to one K(3), one Nb(2), and one Nb(5) atom. In the eleventh Br site, Br(11) is bonded in a 3-coordinate geometry to one K(2), one Nb(3), and one Nb(5) atom. In the twelfth Br site, Br(12) is bonded in a 3-coordinate geometry to one K(1), one Nb(4), and one Nb(6) atom. In the thirteenth Br site, Br(13) is bonded in a 2-coordinate geometry to one K(3), one K(4), one Nb(3), and one Nb(4) atom. In the fourteenth Br site, Br(14) is bonded in a 2-coordinate geometry to one K(1), one K(2), one Nb(1), and one Nb(2) atom. In the fifteenth Br site, Br(15) is bonded in a trigonal planar geometry to one K(1), one K(4), and one Nb(5) atom. In the sixteenth Br site, Br(16) is bonded in a trigonal planar geometry to one K(2), one K(3), and one Nb(6) atom. In the seventeenth Br site, Br(17) is bonded to one K(1), one K(2), one K(3), and one Nb(3) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the eighteenth Br site, Br(18) is bonded to one K(1), one K(2), one K(4), and one Nb(4) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra.
K2(NbBr3)3 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one Br(12), one Br(14), one Br(15), one Br(17), one Br(18), and one Br(2) atom. The K(1)-Br(12) bond length is 3.61 Å. The K(1)-Br(14) bond length is 3.81 Å. The K(1)-Br(15) bond length is 3.18 Å. The K(1)-Br(17) bond length is 3.31 Å. The K(1)-Br(18) bond length is 3.25 Å. The K(1)-Br(2) bond length is 3.24 Å. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Br(1), one Br(11), one Br(14), one Br(16), one Br(17), and one Br(18) atom. The K(2)-Br(1) bond length is 3.24 Å. The K(2)-Br(11) bond length is 3.62 Å. The K(2)-Br(14) bond length is 3.81 Å. The K(2)-Br(16) bond length is 3.18 Å. The K(2)-Br(17) bond length is 3.25 Å. The K(2)-Br(18) bond length is 3.30 Å. In the third K site, K(3) is bonded in a 6-coordinate geometry to one Br(1), one Br(10), one Br(13), one Br(16), one Br(17), and one Br(2) atom. The K(3)-Br(1) bond length is 3.25 Å. The K(3)-Br(10) bond length is 3.62 Å. The K(3)-Br(13) bond length is 3.82 Å. The K(3)-Br(16) bond length is 3.18 Å. The K(3)-Br(17) bond length is 3.24 Å. The K(3)-Br(2) bond length is 3.31 Å. In the fourth K site, K(4) is bonded in a 6-coordinate geometry to one Br(1), one Br(13), one Br(15), one Br(18), one Br(2), and one Br(9) atom. The K(4)-Br(1) bond length is 3.30 Å. The K(4)-Br(13) bond length is 3.81 Å. The K(4)-Br(15) bond length is 3.18 Å. The K(4)-Br(18) bond length is 3.24 Å. The K(4)-Br(2) bond length is 3.26 Å. The K(4)-Br(9) bond length is 3.62 Å. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Br(14), one Br(2), one Br(4), one Br(6), and one Br(9) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(1)-Br(14) bond length is 2.63 Å. The Nb(1)-Br(2) bond length is 2.87 Å. The Nb(1)-Br(4) bond length is 2.63 Å. The Nb(1)-Br(6) bond length is 2.61 Å. The Nb(1)-Br(9) bond length is 2.63 Å. In the second Nb site, Nb(2) is bonded to one Br(1), one Br(10), one Br(14), one Br(3), and one Br(5) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(2)-Br(1) bond length is 2.87 Å. The Nb(2)-Br(10) bond length is 2.63 Å. The Nb(2)-Br(14) bond length is 2.63 Å. The Nb(2)-Br(3) bond length is 2.63 Å. The Nb(2)-Br(5) bond length is 2.61 Å. In the third Nb site, Nb(3) is bonded to one Br(11), one Br(13), one Br(17), one Br(3), and one Br(8) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(3)-Br(11) bond length is 2.63 Å. The Nb(3)-Br(13) bond length is 2.63 Å. The Nb(3)-Br(17) bond length is 2.87 Å. The Nb(3)-Br(3) bond length is 2.62 Å. The Nb(3)-Br(8) bond length is 2.61 Å. In the fourth Nb site, Nb(4) is bonded to one Br(12), one Br(13), one Br(18), one Br(4), and one Br(7) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(4)-Br(12) bond length is 2.63 Å. The Nb(4)-Br(13) bond length is 2.63 Å. The Nb(4)-Br(18) bond length is 2.87 Å. The Nb(4)-Br(4) bond length is 2.63 Å. The Nb(4)-Br(7) bond length is 2.61 Å. In the fifth Nb site, Nb(5) is bonded to one Br(10), one Br(11), one Br(15), one Br(6), and one Br(7) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(5)-Br(10) bond length is 2.63 Å. The Nb(5)-Br(11) bond length is 2.63 Å. The Nb(5)-Br(15) bond length is 2.82 Å. The Nb(5)-Br(6) bond length is 2.61 Å. The Nb(5)-Br(7) bond length is 2.61 Å. In the sixth Nb site, Nb(6) is bonded to one Br(12), one Br(16), one Br(5), one Br(8), and one Br(9) atom to form distorted corner-sharing NbBr5 square pyramids. The Nb(6)-Br(12) bond length is 2.63 Å. The Nb(6)-Br(16) bond length is 2.82 Å. The Nb(6)-Br(5) bond length is 2.61 Å. The Nb(6)-Br(8) bond length is 2.61 Å. The Nb(6)-Br(9) bond length is 2.63 Å. There are eighteen inequivalent Br sites. In the first Br site, Br(1) is bonded to one K(2), one K(3), one K(4), and one Nb(2) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the second Br site, Br(2) is bonded to one K(1), one K(3), one K(4), and one Nb(1) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the third Br site, Br(3) is bonded in a 2-coordinate geometry to one Nb(2) and one Nb(3) atom. In the fourth Br site, Br(4) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(4) atom. In the fifth Br site, Br(5) is bonded in a 2-coordinate geometry to one Nb(2) and one Nb(6) atom. In the sixth Br site, Br(6) is bonded in a 2-coordinate geometry to one Nb(1) and one Nb(5) atom. In the seventh Br site, Br(7) is bonded in a 2-coordinate geometry to one Nb(4) and one Nb(5) atom. In the eighth Br site, Br(8) is bonded in a 2-coordinate geometry to one Nb(3) and one Nb(6) atom. In the ninth Br site, Br(9) is bonded in a 3-coordinate geometry to one K(4), one Nb(1), and one Nb(6) atom. In the tenth Br site, Br(10) is bonded in a 3-coordinate geometry to one K(3), one Nb(2), and one Nb(5) atom. In the eleventh Br site, Br(11) is bonded in a 3-coordinate geometry to one K(2), one Nb(3), and one Nb(5) atom. In the twelfth Br site, Br(12) is bonded in a 3-coordinate geometry to one K(1), one Nb(4), and one Nb(6) atom. In the thirteenth Br site, Br(13) is bonded in a 2-coordinate geometry to one K(3), one K(4), one Nb(3), and one Nb(4) atom. In the fourteenth Br site, Br(14) is bonded in a 2-coordinate geometry to one K(1), one K(2), one Nb(1), and one Nb(2) atom. In the fifteenth Br site, Br(15) is bonded in a trigonal planar geometry to one K(1), one K(4), and one Nb(5) atom. In the sixteenth Br site, Br(16) is bonded in a trigonal planar geometry to one K(2), one K(3), and one Nb(6) atom. In the seventeenth Br site, Br(17) is bonded to one K(1), one K(2), one K(3), and one Nb(3) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra. In the eighteenth Br site, Br(18) is bonded to one K(1), one K(2), one K(4), and one Nb(4) atom to form a mixture of edge and corner-sharing BrK3Nb tetrahedra.