Materials Data on Sr2CaI6 by Materials Project

Abstract

Sr2CaI6 crystallizes in the tetragonal P-4b2 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a body-centered cubic geometry to eight I1- atoms. There are a spread of Sr–I bond distances ranging from 3.34–3.66 Å. In the second Sr2+ site, Sr2+ is bonded in a body-centered cubic geometry to eight I1- atoms. There are a spread of Sr–I bond distances ranging from 3.42–3.57 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted tetrahedral geometry to four equivalent I1- atoms. All Ca–I bond lengths are 3.08 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted square co-planar geometry to four equivalent I1- atoms. All Ca–I bond lengths are 3.11 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to two equivalent Sr2+ and one Ca2+ atom. In the second I1- site, I1- is bonded in a 3-coordinate geometry to two equivalent Sr2+ and one Ca2+ atom. In the third I1- site, I1- is bonded to four Sr2+ atoms to form a mixture of corner and edge-sharing ISr4 tetrahedra.