Materials Data on BaF2 by Materials Project

Abstract

BaF2 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ba2+ is bonded in a 3-coordinate geometry to eleven F1- atoms. There are a spread of Ba–F bond distances ranging from 2.57–3.11 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to six equivalent Ba2+ atoms to form FBa6 octahedra that share corners with twelve equivalent FBa6 octahedra, corners with twelve equivalent FBa5 trigonal bipyramids, edges with six equivalent FBa6 octahedra, faces with two equivalent FBa6 octahedra, and faces with six equivalent FBa5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the second F1- site, F1- is bonded to five equivalent Ba2+ atoms to form distorted FBa5 trigonal bipyramids that share corners with twelve equivalent FBa6 octahedra, corners with eight equivalent FBa5 trigonal bipyramids, edges with six equivalent FBa5 trigonal bipyramids, and faces with six equivalent FBa6 octahedra. The corner-sharing octahedra tilt angles range from 31–59°.