Materials Data on SrCa3Si4 by Materials Project

Abstract

SrCa3Si4 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to seven Si2- atoms. There are a spread of Sr–Si bond distances ranging from 3.16–3.27 Å. There are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven Si2- atoms. There are five shorter (3.13 Å) and two longer (3.19 Å) Ca–Si bond lengths. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven Si2- atoms. There are a spread of Ca–Si bond distances ranging from 3.13–3.33 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven Si2- atoms. There are a spread of Ca–Si bond distances ranging from 3.12–3.17 Å. There are four inequivalent Si2- sites. In the first Si2- site, Si2- is bonded in a 9-coordinate geometry to one Sr2+, six Ca2+, and two equivalent Si2- atoms. Both Si–Si bond lengths are 2.45 Å. In the second Si2- site, Si2- is bonded in a 9-coordinate geometry to two equivalent Sr2+, five Ca2+, and two equivalent Si2- atoms. Both Si–Si bond lengths are 2.45 Å. In the third Si2- site, Si2- is bonded in a 9-coordinate geometry to four equivalent Sr2+, three Ca2+, and two equivalent Si2- atoms. In the fourth Si2- site, Si2- is bonded in a 9-coordinate geometry to seven Ca2+ and two equivalent Si2- atoms.