DOE OSTI2020
W3CuBr7 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are three inequivalent W2+ sites. In the first W2+ site, W2+ is bonded to five Br1- atoms to form edge-sharing WBr5 square pyramids. There are two shorter (2.65 Å) and three longer (2.66 Å) W–Br bond lengths. In the second W2+ site, W2+ is bonded to five Br1- atoms to form edge-sharing WBr5 square pyramids. There are a spread of W–Br bond distances ranging from 2.64–2.68 Å. In the third W2+ site, W2+ is bonded to five Br1- atoms to form edge-sharing WBr5 square pyramids. There are four shorter (2.65 Å) and one longer (2.66 Å) W–Br bond lengths. Cu1+ is bonded in a distorted trigonal planar geometry to four Br1- atoms. There are a spread of Cu–Br bond distances ranging from 2.37–3.38 Å. There are seven inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 12-coordinate geometry to three W2+ atoms. In the second Br1- site, Br1- is bonded in a distorted bent 120 degrees geometry to one W2+ and one Cu1+ atom. In the third Br1- site, Br1- is bonded in a 4-coordinate geometry to three W2+ and one Cu1+ atom. In the fourth Br1- site, Br1- is bonded in a bent 120 degrees geometry to one W2+ and one Cu1+ atom. In the fifth Br1- site, Br1- is bonded in a 5-coordinate geometry to three W2+ atoms. In the sixth Br1- site, Br1- is bonded in a 5-coordinate geometry to three W2+ atoms. In the seventh Br1- site, Br1- is bonded in a water-like geometry to one W2+ and one Cu1+ atom.