Rb2GeS3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent S(2), two equivalent S(3), and three equivalent S(1) atoms to form distorted RbS7 pentagonal bipyramids that share corners with two equivalent Rb(1)S7 pentagonal bipyramids, corners with three equivalent Ge(1)S4 tetrahedra, edges with four equivalent Rb(1)S7 pentagonal bipyramids, and edges with three equivalent Ge(1)S4 tetrahedra. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to two equivalent S(1) and three equivalent S(2) atoms. Ge(1) is bonded to one S(1), one S(2), and two equivalent S(3) atoms to form GeS4 tetrahedra that share corners with three equivalent Rb(1)S7 pentagonal bipyramids, edges with three equivalent Rb(1)S7 pentagonal bipyramids, and  an edgeedge with one Ge(1)S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Rb(2), three equivalent Rb(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SRb5Ge octahedra. The corner-sharing octahedral tilt angles range from 6-75°. In the second S site, S(2) is bonded to two equivalent Rb(1), three equivalent Rb(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SRb5Ge octahedra. The corner-sharing octahedral tilt angles range from 6-75°. In the third S site, S(3) is bonded in a 2-coordinate geometry to two equivalent Rb(1) and two equivalent Ge(1) atoms.
Rb2GeS3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent S(2), two equivalent S(3), and three equivalent S(1) atoms to form distorted RbS7 pentagonal bipyramids that share corners with two equivalent Rb(1)S7 pentagonal bipyramids, corners with three equivalent Ge(1)S4 tetrahedra, edges with four equivalent Rb(1)S7 pentagonal bipyramids, and edges with three equivalent Ge(1)S4 tetrahedra. There is one shorter (3.31 Å) and one longer (3.33 Å) Rb(1)-S(2) bond length. Both Rb(1)-S(3) bond lengths are 3.52 Å. There is one shorter (3.35 Å) and two longer (3.49 Å) Rb(1)-S(1) bond lengths. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to two equivalent S(1) and three equivalent S(2) atoms. There is one shorter (3.38 Å) and one longer (3.51 Å) Rb(2)-S(1) bond length. There is one shorter (3.37 Å) and two longer (3.51 Å) Rb(2)-S(2) bond lengths. Ge(1) is bonded to one S(1), one S(2), and two equivalent S(3) atoms to form GeS4 tetrahedra that share corners with three equivalent Rb(1)S7 pentagonal bipyramids, edges with three equivalent Rb(1)S7 pentagonal bipyramids, and  an edgeedge with one Ge(1)S4 tetrahedra. The Ge(1)-S(1) bond length is 2.16 Å. The Ge(1)-S(2) bond length is 2.16 Å. Both Ge(1)-S(3) bond lengths are 2.30 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Rb(2), three equivalent Rb(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SRb5Ge octahedra. The corner-sharing octahedral tilt angles range from 6-75°. In the second S site, S(2) is bonded to two equivalent Rb(1), three equivalent Rb(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SRb5Ge octahedra. The corner-sharing octahedral tilt angles range from 6-75°. In the third S site, S(3) is bonded in a 2-coordinate geometry to two equivalent Rb(1) and two equivalent Ge(1) atoms.