Materials Data on BaCa2I6 by Materials Project

Abstract

BaCa2I6 crystallizes in the tetragonal P-4b2 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a body-centered cubic geometry to eight equivalent I1- atoms. There are four shorter (3.56 Å) and four longer (3.60 Å) Ba–I bond lengths. In the second Ba2+ site, Ba2+ is bonded in a distorted body-centered cubic geometry to eight equivalent I1- atoms. There are four shorter (3.54 Å) and four longer (3.62 Å) Ba–I bond lengths. There are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six I1- atoms to form distorted corner-sharing CaI6 tetrahedra. There are four shorter (3.12 Å) and two longer (3.83 Å) Ca–I bond lengths. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six I1- atoms. There are a spread of Ca–I bond distances ranging from 3.11–3.42 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one Ca2+ atom. In the second I1- site, I1- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two equivalent Ca2+ atoms. In the third I1- site, I1- is bonded in a 3-coordinate geometry to three Ca2+ atoms.