Materials Data on EuTmCuS3 by Materials Project
TmEuCuS3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with two equivalent TmS6 octahedra, edges with two equivalent TmS6 octahedra, and edges with four equivalent CuS4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are four shorter (2.71 Å) and two longer (2.72 Å) Tm–S bond lengths. Eu2+ is bonded in a 6-coordinate geometry to eight S2- atoms. There are a spread of Eu–S bond distances ranging from 2.93–3.52 Å. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with two equivalent CuS4 tetrahedra and edges with four equivalent TmS6 octahedra. There are two shorter (2.33 Å) and two longer (2.37 Å) Cu–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Tm3+, two equivalent Eu2+, and two equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing SEu2Tm2Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Tm3+, three equivalent Eu2+, and one Cu1+ atom.