Materials Data on BaErCuS3 by Materials Project
BaErCuS3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Ba–S bond distances ranging from 3.15–3.54 Å. Er3+ is bonded to six S2- atoms to form ErS6 octahedra that share corners with two equivalent ErS6 octahedra, edges with two equivalent ErS6 octahedra, and edges with four equivalent CuS4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. There are two shorter (2.70 Å) and four longer (2.75 Å) Er–S bond lengths. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with two equivalent CuS4 tetrahedra and edges with four equivalent ErS6 octahedra. There are two shorter (2.34 Å) and two longer (2.40 Å) Cu–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Er3+, and two equivalent Cu1+ atoms. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Ba2+, two equivalent Er3+, and one Cu1+ atom.