RbSb3Se5 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 12-coordinate geometry to one Sb(1), one Sb(2), two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), one Se(1), one Se(2), one Se(4), and one Se(5) atom. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Rb(1), one Se(3), one Se(4), and one Se(5) atom. In the third Sb site, Sb(3) is bonded in a rectangular see-saw-like geometry to one Se(1), one Se(2), one Se(3), and one Se(5) atom. There are five inequivalent Se sites. In the first Se site, Se(5) is bonded to two equivalent Rb(1), one Sb(1), one Sb(2), and one Sb(3) atom to form distorted corner-sharing SeRb2Sb3 trigonal bipyramids. In the second Se site, Se(1) is bonded in a distorted see-saw-like geometry to two equivalent Rb(1), one Sb(1), and one Sb(3) atom. In the third Se site, Se(2) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Sb(1), and one Sb(3) atom. In the fourth Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Sb(2), and one Sb(3) atom. In the fifth Se site, Se(4) is bonded in an L-shaped geometry to two equivalent Rb(1), one Sb(1), and one Sb(2) atom.
RbSb3Se5 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 12-coordinate geometry to one Sb(1), one Sb(2), two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. The Rb(1)-Sb(1) bond length is 3.97 Å. The Rb(1)-Sb(2) bond length is 4.10 Å. There is one shorter (3.54 Å) and one longer (3.56 Å) Rb(1)-Se(1) bond length. There is one shorter (3.73 Å) and one longer (4.02 Å) Rb(1)-Se(2) bond length. There is one shorter (3.75 Å) and one longer (3.81 Å) Rb(1)-Se(3) bond length. Both Rb(1)-Se(4) bond lengths are 4.04 Å. There is one shorter (3.57 Å) and one longer (3.64 Å) Rb(1)-Se(5) bond length. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), one Se(1), one Se(2), one Se(4), and one Se(5) atom. The Sb(1)-Se(1) bond length is 2.59 Å. The Sb(1)-Se(2) bond length is 2.79 Å. The Sb(1)-Se(4) bond length is 2.60 Å. The Sb(1)-Se(5) bond length is 3.05 Å. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Rb(1), one Se(3), one Se(4), and one Se(5) atom. The Sb(2)-Se(3) bond length is 2.66 Å. The Sb(2)-Se(4) bond length is 2.63 Å. The Sb(2)-Se(5) bond length is 2.55 Å. In the third Sb site, Sb(3) is bonded in a rectangular see-saw-like geometry to one Se(1), one Se(2), one Se(3), and one Se(5) atom. The Sb(3)-Se(1) bond length is 2.75 Å. The Sb(3)-Se(2) bond length is 2.60 Å. The Sb(3)-Se(3) bond length is 2.64 Å. The Sb(3)-Se(5) bond length is 3.15 Å. There are five inequivalent Se sites. In the first Se site, Se(5) is bonded to two equivalent Rb(1), one Sb(1), one Sb(2), and one Sb(3) atom to form distorted corner-sharing SeRb2Sb3 trigonal bipyramids. In the second Se site, Se(1) is bonded in a distorted see-saw-like geometry to two equivalent Rb(1), one Sb(1), and one Sb(3) atom. In the third Se site, Se(2) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Sb(1), and one Sb(3) atom. In the fourth Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Sb(2), and one Sb(3) atom. In the fifth Se site, Se(4) is bonded in an L-shaped geometry to two equivalent Rb(1), one Sb(1), and one Sb(2) atom.