Cs2Hg(BSe)9 crystallizes in the triclinic P-1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one Se(2), one Se(5), one Se(6), one Se(7), one Se(9), two equivalent Se(3), and two equivalent Se(8) atoms. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one B(7), one Se(2), one Se(5), one Se(6), one Se(7), one Se(9), two equivalent Se(1), and two equivalent Se(4) atoms. Hg(1) is bonded in a distorted trigonal planar geometry to one Se(7), one Se(8), and one Se(9) atom. There are nine inequivalent B sites. In the first B site, B(1) is bonded in a distorted single-bond geometry to one B(2), one B(3), one B(4), one B(5), one B(6), and one Se(1) atom. In the second B site, B(2) is bonded in a 6-coordinate geometry to one B(1), one B(3), one B(4), one B(5), one B(6), and one Se(2) atom. In the third B site, B(3) is bonded in a distorted single-bond geometry to one B(1), one B(2), one B(4), one B(5), one B(6), and one Se(3) atom. In the fourth B site, B(4) is bonded in a 6-coordinate geometry to one B(1), one B(2), one B(3), one B(5), one B(6), and one Se(4) atom. In the fifth B site, B(5) is bonded in a 6-coordinate geometry to one B(1), one B(2), one B(3), one B(4), one B(6), and one Se(5) atom. In the sixth B site, B(6) is bonded in a distorted single-bond geometry to one B(1), one B(2), one B(3), one B(4), one B(5), and one Se(6) atom. In the seventh B site, B(7) is bonded in a trigonal planar geometry to one Cs(2), one Se(1), one Se(2), and one Se(7) atom. In the eighth B site, B(8) is bonded in a trigonal planar geometry to one Se(5), one Se(6), and one Se(9) atom. In the ninth B site, B(9) is bonded in a trigonal planar geometry to one Se(3), one Se(4), and one Se(8) atom. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one B(1), and one B(7) atom. In the second Se site, Se(2) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(2), and one B(7) atom. In the third Se site, Se(3) is bonded in a distorted L-shaped geometry to two equivalent Cs(1), one B(3), and one B(9) atom. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one B(4), and one B(9) atom. In the fifth Se site, Se(5) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(5), and one B(8) atom. In the sixth Se site, Se(6) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(6), and one B(8) atom. In the seventh Se site, Se(7) is bonded in a 4-coordinate geometry to one Cs(1), one Cs(2), one Hg(1), and one B(7) atom. In the eighth Se site, Se(8) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Hg(1), and one B(9) atom. In the ninth Se site, Se(9) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Hg(1), and one B(8) atom.
Cs2Hg(BSe)9 crystallizes in the triclinic P-1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one Se(2), one Se(5), one Se(6), one Se(7), one Se(9), two equivalent Se(3), and two equivalent Se(8) atoms. The Cs(1)-Se(2) bond length is 3.84 Å. The Cs(1)-Se(5) bond length is 4.07 Å. The Cs(1)-Se(6) bond length is 3.94 Å. The Cs(1)-Se(7) bond length is 3.64 Å. The Cs(1)-Se(9) bond length is 3.98 Å. There is one shorter (3.74 Å) and one longer (3.84 Å) Cs(1)-Se(3) bond length. There is one shorter (3.81 Å) and one longer (4.06 Å) Cs(1)-Se(8) bond length. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one B(7), one Se(2), one Se(5), one Se(6), one Se(7), one Se(9), two equivalent Se(1), and two equivalent Se(4) atoms. The Cs(2)-B(7) bond length is 3.85 Å. The Cs(2)-Se(2) bond length is 3.87 Å. The Cs(2)-Se(5) bond length is 4.04 Å. The Cs(2)-Se(6) bond length is 3.84 Å. The Cs(2)-Se(7) bond length is 3.91 Å. The Cs(2)-Se(9) bond length is 4.21 Å. There is one shorter (3.82 Å) and one longer (3.92 Å) Cs(2)-Se(1) bond length. There is one shorter (3.80 Å) and one longer (4.00 Å) Cs(2)-Se(4) bond length. Hg(1) is bonded in a distorted trigonal planar geometry to one Se(7), one Se(8), and one Se(9) atom. The Hg(1)-Se(7) bond length is 2.68 Å. The Hg(1)-Se(8) bond length is 2.63 Å. The Hg(1)-Se(9) bond length is 2.60 Å. There are nine inequivalent B sites. In the first B site, B(1) is bonded in a distorted single-bond geometry to one B(2), one B(3), one B(4), one B(5), one B(6), and one Se(1) atom. The B(1)-B(2) bond length is 1.78 Å. The B(1)-B(3) bond length is 1.78 Å. The B(1)-B(4) bond length is 1.80 Å. The B(1)-B(5) bond length is 1.79 Å. The B(1)-B(6) bond length is 1.77 Å. The B(1)-Se(1) bond length is 2.02 Å. In the second B site, B(2) is bonded in a 6-coordinate geometry to one B(1), one B(3), one B(4), one B(5), one B(6), and one Se(2) atom. The B(2)-B(3) bond length is 1.80 Å. The B(2)-B(4) bond length is 1.79 Å. The B(2)-B(5) bond length is 1.80 Å. The B(2)-B(6) bond length is 1.79 Å. The B(2)-Se(2) bond length is 2.03 Å. In the third B site, B(3) is bonded in a distorted single-bond geometry to one B(1), one B(2), one B(4), one B(5), one B(6), and one Se(3) atom. The B(3)-B(4) bond length is 1.78 Å. The B(3)-B(5) bond length is 1.79 Å. The B(3)-B(6) bond length is 1.77 Å. The B(3)-Se(3) bond length is 2.02 Å. In the fourth B site, B(4) is bonded in a 6-coordinate geometry to one B(1), one B(2), one B(3), one B(5), one B(6), and one Se(4) atom. The B(4)-B(5) bond length is 1.80 Å. The B(4)-B(6) bond length is 1.79 Å. The B(4)-Se(4) bond length is 2.02 Å. In the fifth B site, B(5) is bonded in a 6-coordinate geometry to one B(1), one B(2), one B(3), one B(4), one B(6), and one Se(5) atom. The B(5)-B(6) bond length is 1.78 Å. The B(5)-Se(5) bond length is 2.03 Å. In the sixth B site, B(6) is bonded in a distorted single-bond geometry to one B(1), one B(2), one B(3), one B(4), one B(5), and one Se(6) atom. The B(6)-Se(6) bond length is 2.02 Å. In the seventh B site, B(7) is bonded in a trigonal planar geometry to one Cs(2), one Se(1), one Se(2), and one Se(7) atom. The B(7)-Se(1) bond length is 1.97 Å. The B(7)-Se(2) bond length is 1.99 Å. The B(7)-Se(7) bond length is 1.94 Å. In the eighth B site, B(8) is bonded in a trigonal planar geometry to one Se(5), one Se(6), and one Se(9) atom. The B(8)-Se(5) bond length is 1.98 Å. The B(8)-Se(6) bond length is 1.98 Å. The B(8)-Se(9) bond length is 1.95 Å. In the ninth B site, B(9) is bonded in a trigonal planar geometry to one Se(3), one Se(4), and one Se(8) atom. The B(9)-Se(3) bond length is 1.97 Å. The B(9)-Se(4) bond length is 1.98 Å. The B(9)-Se(8) bond length is 1.94 Å. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one B(1), and one B(7) atom. In the second Se site, Se(2) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(2), and one B(7) atom. In the third Se site, Se(3) is bonded in a distorted L-shaped geometry to two equivalent Cs(1), one B(3), and one B(9) atom. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one B(4), and one B(9) atom. In the fifth Se site, Se(5) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(5), and one B(8) atom. In the sixth Se site, Se(6) is bonded in a distorted L-shaped geometry to one Cs(1), one Cs(2), one B(6), and one B(8) atom. In the seventh Se site, Se(7) is bonded in a 4-coordinate geometry to one Cs(1), one Cs(2), one Hg(1), and one B(7) atom. In the eighth Se site, Se(8) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Hg(1), and one B(9) atom. In the ninth Se site, Se(9) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Hg(1), and one B(8) atom.