Materials Data on CsEr2Cu3S5 by Materials Project

Abstract

CsEr2Cu3S5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Cs–S bond distances ranging from 3.38–3.56 Å. Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share a cornercorner with one ErS6 octahedra, corners with four equivalent CuS4 tetrahedra, edges with four equivalent ErS6 octahedra, and edges with five CuS4 tetrahedra. The corner-sharing octahedral tilt angles are 24°. There are a spread of Er–S bond distances ranging from 2.69–2.79 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with four equivalent ErS6 octahedra, corners with four CuS4 tetrahedra, edges with three equivalent ErS6 octahedra, and an edgeedge with one CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–58°. There are a spread of Cu–S bond distances ranging from 2.37–2.43 Å. In the second Cu1+ site, Cu1+ is bonded to four S2- atoms to form distorted CuS4 tetrahedra that share corners with six CuS4 tetrahedra and edges with four equivalent ErS6 octahedra. There are two shorter (2.24 Å) and two longer (2.70 Å) Cu–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to one Cs1+, three equivalent Er3+, and two equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing SCsEr3Cu2 octahedra. The corner-sharing octahedral tilt angles are 52°. In the second S2- site, S2- is bonded in a 7-coordinate geometry to two equivalent Cs1+, two equivalent Er3+, and three Cu1+ atoms. In the third S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Cs1+, two equivalent Er3+, and two equivalent Cu1+ atoms.