Materials Data on SrCaI4 by Materials Project

SrCaI4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six I1- atoms to form SrI6 octahedra that share corners with four CaI6 octahedra, edges with two equivalent SrI6 octahedra, and edges with three CaI6 octahedra. The corner-sharing octahedra tilt angles range from 10–19°. There are a spread of Sr–I bond distances ranging from 3.14–3.44 Å. In the second Sr2+ site, Sr2+ is bonded to six I1- atoms to form SrI6 octahedra that share corners with four CaI6 octahedra, edges with two equivalent CaI6 octahedra, and edges with three SrI6 octahedra. The corner-sharing octahedra tilt angles range from 10–18°. There are a spread of Sr–I bond distances ranging from 3.14–3.45 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six I1- atoms to form CaI6 octahedra that share corners with four SrI6 octahedra, edges with two equivalent CaI6 octahedra, and edges with three SrI6 octahedra. The corner-sharing octahedra tilt angles range from 10–19°. There are a spread of Ca–I bond distances ranging from 2.99–3.29 Å. In the second Ca2+ site, Ca2+ is bonded to six I1- atoms to form CaI6 octahedra that share corners with four SrI6 octahedra, edges with two equivalent SrI6 octahedra, and edges with three CaI6 octahedra. The corner-sharing octahedra tilt angles range from 10–18°. There are a spread of Ca–I bond distances ranging from 2.99–3.29 Å. There are five inequivalent I1- sites. In the first I1- site, I1- is bonded in a linear geometry to one Sr2+ and one Ca2+ atom. In the second I1- site, I1- is bonded in a linear geometry to one Sr2+ and one Ca2+ atom. In the third I1- site, I1- is bonded in a distorted see-saw-like geometry to three Sr2+ and one Ca2+ atom. In the fourth I1- site, I1- is bonded in a distorted see-saw-like geometry to one Sr2+ and three Ca2+ atoms. In the fifth I1- site, I1- is bonded in a distorted see-saw-like geometry to two Sr2+ and two Ca2+ atoms.