SiBa2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to two equivalent S(3), three equivalent S(2), and four equivalent S(1) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one S(2), three equivalent S(3), and four equivalent S(1) atoms. Si(1) is bonded in a tetrahedral geometry to one S(2), one S(3), and two equivalent S(1) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second S site, S(2) is bonded to one Ba(2), three equivalent Ba(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing SBa4Si trigonal bipyramids. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), and one Si(1) atom.
SiBa2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to two equivalent S(3), three equivalent S(2), and four equivalent S(1) atoms. There is one shorter (3.12 Å) and one longer (3.33 Å) Ba(1)-S(3) bond length. There is one shorter (3.26 Å) and two longer (3.55 Å) Ba(1)-S(2) bond lengths. There are two shorter (3.23 Å) and two longer (3.29 Å) Ba(1)-S(1) bond lengths. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one S(2), three equivalent S(3), and four equivalent S(1) atoms. The Ba(2)-S(2) bond length is 3.28 Å. There are two shorter (3.45 Å) and one longer (3.56 Å) Ba(2)-S(3) bond length. There are two shorter (3.31 Å) and two longer (3.37 Å) Ba(2)-S(1) bond lengths. Si(1) is bonded in a tetrahedral geometry to one S(2), one S(3), and two equivalent S(1) atoms. The Si(1)-S(2) bond length is 2.11 Å. The Si(1)-S(3) bond length is 2.13 Å. Both Si(1)-S(1) bond lengths are 2.11 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second S site, S(2) is bonded to one Ba(2), three equivalent Ba(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing SBa4Si trigonal bipyramids. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), three equivalent Ba(2), and one Si(1) atom.