Materials Data on Ca4SiP4 by Materials Project
Ca4SiP4 crystallizes in the cubic P-43n space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to one Si4- and six P1- atoms. The Ca–Si bond length is 3.00 Å. There are three shorter (2.94 Å) and three longer (3.09 Å) Ca–P bond lengths. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to one Si4- and six P1- atoms. The Ca–Si bond length is 2.98 Å. There are a spread of Ca–P bond distances ranging from 2.91–3.10 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a distorted body-centered cubic geometry to four equivalent Ca2+ and four equivalent P1- atoms. All Si–P bond lengths are 2.27 Å. In the second Si4- site, Si4- is bonded in a distorted body-centered cubic geometry to four equivalent Ca2+ and four equivalent P1- atoms. All Si–P bond lengths are 2.26 Å. There are two inequivalent P1- sites. In the first P1- site, P1- is bonded in a 7-coordinate geometry to six Ca2+ and one Si4- atom. In the second P1- site, P1- is bonded to six Ca2+ and one Si4- atom to form a mixture of distorted corner, edge, and face-sharing PCa6Si pentagonal bipyramids.