Rb3AsSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one Se(3), two equivalent Se(2), and four equivalent Se(1) atoms. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms. As(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Rb(1), three equivalent Rb(2), and one As(1) atom. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent Rb(1), four equivalent Rb(2), and one As(1) atom. In the third Se site, Se(3) is bonded to one Rb(1), four equivalent Rb(2), and one As(1) atom to form edge-sharing SeRb5As octahedra.
Rb3AsSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one Se(3), two equivalent Se(2), and four equivalent Se(1) atoms. The Rb(1)-Se(3) bond length is 3.41 Å. There is one shorter (3.58 Å) and one longer (3.59 Å) Rb(1)-Se(2) bond length. There are two shorter (3.54 Å) and two longer (3.97 Å) Rb(1)-Se(1) bond lengths. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms. There is one shorter (3.56 Å) and one longer (3.77 Å) Rb(2)-Se(2) bond length. There is one shorter (3.41 Å) and one longer (3.48 Å) Rb(2)-Se(3) bond length. There are a spread of Rb(2)-Se(1) bond distances ranging from 3.55-3.73 Å. As(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. The As(1)-Se(2) bond length is 2.34 Å. The As(1)-Se(3) bond length is 2.32 Å. Both As(1)-Se(1) bond lengths are 2.33 Å. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Rb(1), three equivalent Rb(2), and one As(1) atom. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent Rb(1), four equivalent Rb(2), and one As(1) atom. In the third Se site, Se(3) is bonded to one Rb(1), four equivalent Rb(2), and one As(1) atom to form edge-sharing SeRb5As octahedra.