Nb6Pd2Se15 crystallizes in the triclinic P-1 space group. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Se(12), one Se(13), one Se(15), one Se(7), one Se(9), and two equivalent Se(10) atoms to form a mixture of distorted face and edge-sharing NbSe7 pentagonal bipyramids. In the second Nb site, Nb(2) is bonded to one Se(12), one Se(13), one Se(14), one Se(7), one Se(8), and two equivalent Se(11) atoms to form a mixture of distorted face and edge-sharing NbSe7 pentagonal bipyramids. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to one Se(10), one Se(11), one Se(12), one Se(14), one Se(15), one Se(8), and one Se(9) atom. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one Se(1), one Se(13), one Se(2), one Se(5), one Se(6), and one Se(7) atom. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to one Se(14), one Se(2), one Se(3), one Se(4), one Se(6), and one Se(8) atom. In the sixth Nb site, Nb(6) is bonded in a 6-coordinate geometry to one Se(1), one Se(15), one Se(3), one Se(4), one Se(5), and one Se(9) atom. There are three inequivalent Pd sites. In the first Pd site, Pd(1) is bonded in a square co-planar geometry to two equivalent Se(1) and two equivalent Se(5) atoms. In the second Pd site, Pd(2) is bonded in a square co-planar geometry to one Se(2), one Se(3), one Se(4), and one Se(6) atom. In the third Pd site, Pd(3) is bonded in a 4-coordinate geometry to two equivalent Se(10) and two equivalent Se(11) atoms. There are fifteen inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(6), and one Pd(1) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(5), and one Pd(2) atom. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to one Nb(5), one Nb(6), and one Pd(2) atom. In the fourth Se site, Se(4) is bonded in a distorted T-shaped geometry to one Nb(5), one Nb(6), and one Pd(2) atom. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(6), and one Pd(1) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(5), and one Pd(2) atom. In the seventh Se site, Se(7) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the eighth Se site, Se(8) is bonded in a distorted T-shaped geometry to one Nb(2), one Nb(3), and one Nb(5) atom. In the ninth Se site, Se(9) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(3), and one Nb(6) atom. In the tenth Se site, Se(10) is bonded in a 4-coordinate geometry to one Nb(3), two equivalent Nb(1), and one Pd(3) atom. In the eleventh Se site, Se(11) is bonded in a 4-coordinate geometry to one Nb(3), two equivalent Nb(2), and one Pd(3) atom. In the twelfth Se site, Se(12) is bonded in a distorted trigonal non-coplanar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the thirteenth Se site, Se(13) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the fourteenth Se site, Se(14) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(3), and one Nb(5) atom. In the fifteenth Se site, Se(15) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(6) atom.
Nb6Pd2Se15 crystallizes in the triclinic P-1 space group. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one Se(12), one Se(13), one Se(15), one Se(7), one Se(9), and two equivalent Se(10) atoms to form a mixture of distorted face and edge-sharing NbSe7 pentagonal bipyramids. The Nb(1)-Se(12) bond length is 2.65 Å. The Nb(1)-Se(13) bond length is 2.61 Å. The Nb(1)-Se(15) bond length is 2.62 Å. The Nb(1)-Se(7) bond length is 2.63 Å. The Nb(1)-Se(9) bond length is 2.65 Å. There is one shorter (2.68 Å) and one longer (2.81 Å) Nb(1)-Se(10) bond length. In the second Nb site, Nb(2) is bonded to one Se(12), one Se(13), one Se(14), one Se(7), one Se(8), and two equivalent Se(11) atoms to form a mixture of distorted face and edge-sharing NbSe7 pentagonal bipyramids. The Nb(2)-Se(12) bond length is 2.65 Å. The Nb(2)-Se(13) bond length is 2.61 Å. The Nb(2)-Se(14) bond length is 2.62 Å. The Nb(2)-Se(7) bond length is 2.63 Å. The Nb(2)-Se(8) bond length is 2.64 Å. There is one shorter (2.68 Å) and one longer (2.81 Å) Nb(2)-Se(11) bond length. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to one Se(10), one Se(11), one Se(12), one Se(14), one Se(15), one Se(8), and one Se(9) atom. The Nb(3)-Se(10) bond length is 2.69 Å. The Nb(3)-Se(11) bond length is 2.69 Å. The Nb(3)-Se(12) bond length is 2.78 Å. The Nb(3)-Se(14) bond length is 2.64 Å. The Nb(3)-Se(15) bond length is 2.64 Å. The Nb(3)-Se(8) bond length is 2.64 Å. The Nb(3)-Se(9) bond length is 2.64 Å. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one Se(1), one Se(13), one Se(2), one Se(5), one Se(6), and one Se(7) atom. The Nb(4)-Se(1) bond length is 2.62 Å. The Nb(4)-Se(13) bond length is 2.62 Å. The Nb(4)-Se(2) bond length is 2.61 Å. The Nb(4)-Se(5) bond length is 2.60 Å. The Nb(4)-Se(6) bond length is 2.60 Å. The Nb(4)-Se(7) bond length is 2.61 Å. In the fifth Nb site, Nb(5) is bonded in a 6-coordinate geometry to one Se(14), one Se(2), one Se(3), one Se(4), one Se(6), and one Se(8) atom. The Nb(5)-Se(14) bond length is 2.60 Å. The Nb(5)-Se(2) bond length is 2.60 Å. The Nb(5)-Se(3) bond length is 2.61 Å. The Nb(5)-Se(4) bond length is 2.60 Å. The Nb(5)-Se(6) bond length is 2.60 Å. The Nb(5)-Se(8) bond length is 2.62 Å. In the sixth Nb site, Nb(6) is bonded in a 6-coordinate geometry to one Se(1), one Se(15), one Se(3), one Se(4), one Se(5), and one Se(9) atom. The Nb(6)-Se(1) bond length is 2.60 Å. The Nb(6)-Se(15) bond length is 2.60 Å. The Nb(6)-Se(3) bond length is 2.61 Å. The Nb(6)-Se(4) bond length is 2.60 Å. The Nb(6)-Se(5) bond length is 2.60 Å. The Nb(6)-Se(9) bond length is 2.62 Å. There are three inequivalent Pd sites. In the first Pd site, Pd(1) is bonded in a square co-planar geometry to two equivalent Se(1) and two equivalent Se(5) atoms. Both Pd(1)-Se(1) bond lengths are 2.46 Å. Both Pd(1)-Se(5) bond lengths are 2.45 Å. In the second Pd site, Pd(2) is bonded in a square co-planar geometry to one Se(2), one Se(3), one Se(4), and one Se(6) atom. The Pd(2)-Se(2) bond length is 2.46 Å. The Pd(2)-Se(3) bond length is 2.46 Å. The Pd(2)-Se(4) bond length is 2.45 Å. The Pd(2)-Se(6) bond length is 2.45 Å. In the third Pd site, Pd(3) is bonded in a 4-coordinate geometry to two equivalent Se(10) and two equivalent Se(11) atoms. Both Pd(3)-Se(10) bond lengths are 2.61 Å. Both Pd(3)-Se(11) bond lengths are 2.61 Å. There are fifteen inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(6), and one Pd(1) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(5), and one Pd(2) atom. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to one Nb(5), one Nb(6), and one Pd(2) atom. In the fourth Se site, Se(4) is bonded in a distorted T-shaped geometry to one Nb(5), one Nb(6), and one Pd(2) atom. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(6), and one Pd(1) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Nb(4), one Nb(5), and one Pd(2) atom. In the seventh Se site, Se(7) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the eighth Se site, Se(8) is bonded in a distorted T-shaped geometry to one Nb(2), one Nb(3), and one Nb(5) atom. In the ninth Se site, Se(9) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(3), and one Nb(6) atom. In the tenth Se site, Se(10) is bonded in a 4-coordinate geometry to one Nb(3), two equivalent Nb(1), and one Pd(3) atom. In the eleventh Se site, Se(11) is bonded in a 4-coordinate geometry to one Nb(3), two equivalent Nb(2), and one Pd(3) atom. In the twelfth Se site, Se(12) is bonded in a distorted trigonal non-coplanar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the thirteenth Se site, Se(13) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the fourteenth Se site, Se(14) is bonded in a 3-coordinate geometry to one Nb(2), one Nb(3), and one Nb(5) atom. In the fifteenth Se site, Se(15) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(6) atom.