Materials Data on K3CuP2S7 by Materials Project
K3CuP2S7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.17–3.72 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.21–3.53 Å. In the third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.31–3.61 Å. Cu1+ is bonded in a trigonal planar geometry to three S2- atoms. There are a spread of Cu–S bond distances ranging from 2.21–2.26 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 2.01–2.16 Å. In the second P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 2.01–2.18 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the second S2- site, S2- is bonded in a 2-coordinate geometry to three K1+, one Cu1+, and one P5+ atom. In the third S2- site, S2- is bonded in a distorted water-like geometry to two K1+ and two P5+ atoms. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one P5+ atom. In the fifth S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Cu1+, and one P5+ atom. In the sixth S2- site, S2- is bonded to four K1+ and one P5+ atom to form distorted corner-sharing SK4P trigonal bipyramids. In the seventh S2- site, S2- is bonded in a 2-coordinate geometry to three K1+, one Cu1+, and one P5+ atom.