Gd3Si2S8Br crystallizes in the monoclinic C2/c space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 9-coordinate geometry to one S(3), two equivalent S(1), two equivalent S(4), three equivalent S(2), and one Br(1) atom. In the second Gd site, Gd(2) is bonded in a 9-coordinate geometry to two equivalent S(1), two equivalent S(4), four equivalent S(3), and one Br(1) atom. Si(1) is bonded in a tetrahedral geometry to one S(1), one S(2), one S(3), and one S(4) atom. There are four inequivalent S sites. In the first S site, S(4) is bonded to one Gd(2), two equivalent Gd(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SGd3Si trigonal pyramids. In the second S site, S(1) is bonded to one Gd(2), two equivalent Gd(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SGd3Si trigonal pyramids. In the third S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Gd(1) and one Si(1) atom. In the fourth S site, S(3) is bonded in a 4-coordinate geometry to one Gd(1), two equivalent Gd(2), and one Si(1) atom. Br(1) is bonded in a distorted single-bond geometry to one Gd(2) and two equivalent Gd(1) atoms.
Gd3Si2S8Br crystallizes in the monoclinic C2/c space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 9-coordinate geometry to one S(3), two equivalent S(1), two equivalent S(4), three equivalent S(2), and one Br(1) atom. The Gd(1)-S(3) bond length is 2.88 Å. There is one shorter (2.95 Å) and one longer (3.07 Å) Gd(1)-S(1) bond length. There is one shorter (2.89 Å) and one longer (2.98 Å) Gd(1)-S(4) bond length. There are a spread of Gd(1)-S(2) bond distances ranging from 2.88-3.00 Å. The Gd(1)-Br(1) bond length is 3.45 Å. In the second Gd site, Gd(2) is bonded in a 9-coordinate geometry to two equivalent S(1), two equivalent S(4), four equivalent S(3), and one Br(1) atom. Both Gd(2)-S(1) bond lengths are 2.87 Å. Both Gd(2)-S(4) bond lengths are 2.87 Å. There are two shorter (3.12 Å) and two longer (3.52 Å) Gd(2)-S(3) bond lengths. The Gd(2)-Br(1) bond length is 2.92 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 2.13 Å. The Si(1)-S(2) bond length is 2.13 Å. The Si(1)-S(3) bond length is 2.12 Å. The Si(1)-S(4) bond length is 2.13 Å. There are four inequivalent S sites. In the first S site, S(4) is bonded to one Gd(2), two equivalent Gd(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SGd3Si trigonal pyramids. In the second S site, S(1) is bonded to one Gd(2), two equivalent Gd(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SGd3Si trigonal pyramids. In the third S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Gd(1) and one Si(1) atom. In the fourth S site, S(3) is bonded in a 4-coordinate geometry to one Gd(1), two equivalent Gd(2), and one Si(1) atom. Br(1) is bonded in a distorted single-bond geometry to one Gd(2) and two equivalent Gd(1) atoms.