KBiSiS4 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one S(4), two equivalent S(1), two equivalent S(3), and three equivalent S(2) atoms. Si(1) is bonded in a tetrahedral geometry to one S(1), one S(2), one S(3), and one S(4) atom. Bi(1) is bonded in a 7-coordinate geometry to one S(2), two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded in a distorted single-bond geometry to two equivalent K(1), one Si(1), and two equivalent Bi(1) atoms. In the second S site, S(2) is bonded to three equivalent K(1), one Si(1), and one Bi(1) atom to form a mixture of distorted edge and corner-sharing SK3SiBi trigonal bipyramids. In the third S site, S(3) is bonded in a 5-coordinate geometry to two equivalent K(1), one Si(1), and two equivalent Bi(1) atoms. In the fourth S site, S(4) is bonded in a distorted see-saw-like geometry to one K(1), one Si(1), and two equivalent Bi(1) atoms.
KBiSiS4 crystallizes in the monoclinic P2_1/c space group. K(1) is bonded in a 8-coordinate geometry to one S(4), two equivalent S(1), two equivalent S(3), and three equivalent S(2) atoms. The K(1)-S(4) bond length is 3.28 Å. There is one shorter (3.33 Å) and one longer (3.34 Å) K(1)-S(1) bond length. There is one shorter (3.36 Å) and one longer (3.49 Å) K(1)-S(3) bond length. There are a spread of K(1)-S(2) bond distances ranging from 3.26-3.54 Å. Si(1) is bonded in a tetrahedral geometry to one S(1), one S(2), one S(3), and one S(4) atom. The Si(1)-S(1) bond length is 2.11 Å. The Si(1)-S(2) bond length is 2.11 Å. The Si(1)-S(3) bond length is 2.13 Å. The Si(1)-S(4) bond length is 2.15 Å. Bi(1) is bonded in a 7-coordinate geometry to one S(2), two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms. The Bi(1)-S(2) bond length is 2.78 Å. There is one shorter (2.90 Å) and one longer (3.19 Å) Bi(1)-S(1) bond length. There is one shorter (2.74 Å) and one longer (3.18 Å) Bi(1)-S(3) bond length. There is one shorter (2.79 Å) and one longer (2.95 Å) Bi(1)-S(4) bond length. There are four inequivalent S sites. In the first S site, S(1) is bonded in a distorted single-bond geometry to two equivalent K(1), one Si(1), and two equivalent Bi(1) atoms. In the second S site, S(2) is bonded to three equivalent K(1), one Si(1), and one Bi(1) atom to form a mixture of distorted edge and corner-sharing SK3SiBi trigonal bipyramids. In the third S site, S(3) is bonded in a 5-coordinate geometry to two equivalent K(1), one Si(1), and two equivalent Bi(1) atoms. In the fourth S site, S(4) is bonded in a distorted see-saw-like geometry to one K(1), one Si(1), and two equivalent Bi(1) atoms.