Materials Data on U3Cu2S7 by Materials Project
U3Cu2S7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. U4+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of U–S bond distances ranging from 2.64–3.09 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four S2- atoms. All Cu–S bond lengths are 2.26 Å. In the second Cu1+ site, Cu1+ is bonded in a trigonal planar geometry to three equivalent S2- atoms. All Cu–S bond lengths are 2.20 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted tetrahedral geometry to three equivalent U4+ and one Cu1+ atom. In the second S2- site, S2- is bonded in a 4-coordinate geometry to three equivalent U4+ and one Cu1+ atom. In the third S2- site, S2- is bonded in a 1-coordinate geometry to four equivalent U4+ and one Cu1+ atom.