Rb2AgSbS4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. Ag(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form distorted AgS4 tetrahedra that share corners with two equivalent Sb(1)S4 tetrahedra and  an edgeedge with one Sb(1)S4 tetrahedra. Sb(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form SbS4 tetrahedra that share corners with two equivalent Ag(1)S4 tetrahedra and  an edgeedge with one Ag(1)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the second S site, S(2) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the fourth S site, S(4) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom.
Rb2AgSbS4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. The Rb(1)-S(1) bond length is 3.35 Å. There is one shorter (3.53 Å) and one longer (3.75 Å) Rb(1)-S(2) bond length. There is one shorter (3.41 Å) and one longer (3.44 Å) Rb(1)-S(3) bond length. There is one shorter (3.48 Å) and one longer (3.55 Å) Rb(1)-S(4) bond length. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There is one shorter (3.52 Å) and one longer (3.88 Å) Rb(2)-S(1) bond length. There is one shorter (3.52 Å) and one longer (3.67 Å) Rb(2)-S(2) bond length. There is one shorter (3.42 Å) and one longer (3.76 Å) Rb(2)-S(3) bond length. There is one shorter (3.43 Å) and one longer (3.72 Å) Rb(2)-S(4) bond length. Ag(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form distorted AgS4 tetrahedra that share corners with two equivalent Sb(1)S4 tetrahedra and  an edgeedge with one Sb(1)S4 tetrahedra. The Ag(1)-S(1) bond length is 2.54 Å. The Ag(1)-S(2) bond length is 2.57 Å. The Ag(1)-S(3) bond length is 2.72 Å. The Ag(1)-S(4) bond length is 2.77 Å. Sb(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form SbS4 tetrahedra that share corners with two equivalent Ag(1)S4 tetrahedra and  an edgeedge with one Ag(1)S4 tetrahedra. The Sb(1)-S(1) bond length is 2.37 Å. The Sb(1)-S(2) bond length is 2.39 Å. The Sb(1)-S(3) bond length is 2.37 Å. The Sb(1)-S(4) bond length is 2.37 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the second S site, S(2) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom. In the fourth S site, S(4) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Ag(1), and one Sb(1) atom.