Materials Data on RbSm2CuS4 by Materials Project
RbSm2CuS4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Rb1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Rb–S bond distances ranging from 3.26–3.80 Å. Sm3+ is bonded to six S2- atoms to form SmS6 octahedra that share corners with three equivalent SmS6 octahedra, a cornercorner with one CuS4 tetrahedra, edges with five equivalent SmS6 octahedra, and edges with two equivalent CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–35°. There are a spread of Sm–S bond distances ranging from 2.76–2.90 Å. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with two equivalent SmS6 octahedra, corners with two equivalent CuS4 tetrahedra, and edges with four equivalent SmS6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are two shorter (2.35 Å) and two longer (2.38 Å) Cu–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Rb1+ and four equivalent Sm3+ atoms to form a mixture of distorted edge and corner-sharing SRb2Sm4 octahedra. The corner-sharing octahedra tilt angles range from 3–46°. In the second S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Rb1+, two equivalent Sm3+, and two equivalent Cu1+ atoms. In the third S2- site, S2- is bonded to two equivalent Rb1+, three equivalent Sm3+, and one Cu1+ atom to form distorted SRb2Sm3Cu octahedra that share corners with six SRb2Sm4 octahedra, edges with seven SRb2Sm4 octahedra, and a faceface with one SRb2Sm3Cu octahedra. The corner-sharing octahedra tilt angles range from 3–67°.