Materials Data on Sr2UCu2S5 by Materials Project

Abstract

Sr2UCu2S5 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Sr–S bond distances ranging from 2.98–3.62 Å. U4+ is bonded to six S2- atoms to form US6 octahedra that share edges with two equivalent US6 octahedra and edges with four equivalent CuS4 tetrahedra. There are two shorter (2.70 Å) and four longer (2.76 Å) U–S bond lengths. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with three equivalent CuS4 tetrahedra and edges with two equivalent US6 octahedra. There are a spread of Cu–S bond distances ranging from 2.33–2.37 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three equivalent Sr2+, one U4+, and two equivalent Cu1+ atoms. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Sr2+, two equivalent U4+, and one Cu1+ atom. In the third S2- site, S2- is bonded to four equivalent Sr2+ and two equivalent Cu1+ atoms to form edge-sharing SSr4Cu2 octahedra.