Materials Data on CaWF5 by Materials Project

Abstract

CaWF5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ca2+ is bonded to seven F1- atoms to form distorted CaF7 pentagonal bipyramids that share corners with four equivalent WF6 octahedra, edges with two equivalent WF6 octahedra, and edges with two equivalent CaF7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 11–47°. There are a spread of Ca–F bond distances ranging from 2.21–2.55 Å. W3+ is bonded to six F1- atoms to form WF6 octahedra that share corners with two equivalent WF6 octahedra, corners with four equivalent CaF7 pentagonal bipyramids, and edges with two equivalent CaF7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 41°. There are a spread of W–F bond distances ranging from 2.08–2.14 Å. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca2+ and one W3+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent Ca2+ and one W3+ atom. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to one Ca2+ and one W3+ atom. In the fourth F1- site, F1- is bonded in a linear geometry to one Ca2+ and one W3+ atom. In the fifth F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+ and two equivalent W3+ atoms.