Materials Data on Ba2CaI6 by Materials Project

Abstract

Ba2CaI6 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 9-coordinate geometry to eight I1- atoms. There are a spread of Ba–I bond distances ranging from 3.51–3.94 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight I1- atoms. There are a spread of Ba–I bond distances ranging from 3.55–3.80 Å. Ca2+ is bonded to six I1- atoms to form edge-sharing CaI6 octahedra. There are a spread of Ca–I bond distances ranging from 3.03–3.18 Å. There are six inequivalent I1- sites. In the first I1- site, I1- is bonded in a 4-coordinate geometry to two Ba2+ and two equivalent Ca2+ atoms. In the second I1- site, I1- is bonded to three Ba2+ and one Ca2+ atom to form distorted IBa3Ca trigonal pyramids that share corners with two equivalent IBa4 tetrahedra, corners with two equivalent IBa3Ca trigonal pyramids, and edges with two equivalent IBa4 tetrahedra. In the third I1- site, I1- is bonded to four Ba2+ atoms to form distorted IBa4 tetrahedra that share corners with two equivalent IBa4 tetrahedra, corners with two equivalent IBa3Ca trigonal pyramids, an edgeedge with one IBa4 tetrahedra, and edges with two equivalent IBa3Ca trigonal pyramids. In the fourth I1- site, I1- is bonded in a 3-coordinate geometry to two Ba2+ and one Ca2+ atom. 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 1-coordinate geometry to three Ba2+ and one Ca2+ atom.