Materials Data on Cu4SiP8 by Materials Project
Cu4SiP8 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Cu1+ is bonded in a 4-coordinate geometry to four P atoms. There are a spread of Cu–P bond distances ranging from 2.28–2.56 Å. Si4- is bonded to four equivalent P atoms to form SiP4 tetrahedra that share corners with four equivalent PCuP3 tetrahedra. All Si–P bond lengths are 2.26 Å. There are two inequivalent P sites. In the first P site, P is bonded to three equivalent Cu1+, one Si4-, and one P atom to form distorted PCu3SiP trigonal bipyramids that share corners with five equivalent PCuP3 tetrahedra, corners with seven equivalent PCu3SiP trigonal bipyramids, and an edgeedge with one PCu3SiP trigonal bipyramid. The P–P bond length is 2.19 Å. In the second P site, P is bonded to one Cu1+ and three P atoms to form distorted PCuP3 tetrahedra that share a cornercorner with one SiP4 tetrahedra, corners with two equivalent PCuP3 tetrahedra, and corners with five equivalent PCu3SiP trigonal bipyramids. Both P–P bond lengths are 2.23 Å.