Materials Data on BaCaI4 by Materials Project

Abstract

BaCaI4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven I1- atoms. There are a spread of Ba–I bond distances ranging from 3.37–3.97 Å. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to eight I1- atoms. There are a spread of Ba–I bond distances ranging from 3.52–4.22 Å. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six I1- atoms to form a mixture of edge and corner-sharing CaI6 octahedra. The corner-sharing octahedra tilt angles range from 45–46°. There are a spread of Ca–I bond distances ranging from 3.06–3.29 Å. In the second Ca2+ site, Ca2+ is bonded to six I1- atoms to form a mixture of edge and corner-sharing CaI6 octahedra. The corner-sharing octahedra tilt angles range from 45–46°. There are a spread of Ca–I bond distances ranging from 3.08–3.38 Å. There are eight inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to one Ba2+ and two Ca2+ atoms. In the second I1- site, I1- is bonded in a 4-coordinate geometry to two Ba2+ and two Ca2+ atoms. In the third I1- site, I1- is bonded in a 4-coordinate geometry to two Ba2+ and two equivalent Ca2+ atoms. In the fourth I1- site, I1- is bonded to two Ba2+ and two equivalent Ca2+ atoms to form distorted edge-sharing IBa2Ca2 tetrahedra. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to two Ba2+ and one Ca2+ atom. In the sixth I1- site, I1- is bonded in a 2-coordinate geometry to two Ba2+ and one Ca2+ atom. In the seventh I1- site, I1- is bonded in a 3-coordinate geometry to two Ba2+ and one Ca2+ atom. In the eighth I1- site, I1- is bonded in a 3-coordinate geometry to two Ba2+ and one Ca2+ atom.