Materials Data on CsGeI3 by Materials Project

Abstract

CsGeI3 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Cs1+ is bonded to twelve I1- atoms to form distorted CsI12 cuboctahedra that share corners with twelve equivalent CsI12 cuboctahedra, faces with six equivalent CsI12 cuboctahedra, and faces with eight equivalent GeI6 octahedra. There are a spread of Cs–I bond distances ranging from 4.16–4.61 Å. Ge2+ is bonded to six I1- atoms to form distorted GeI6 octahedra that share corners with six equivalent GeI6 octahedra and faces with eight equivalent CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–19°. There are a spread of Ge–I bond distances ranging from 2.77–3.49 Å. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 6-coordinate geometry to four equivalent Cs1+ and two equivalent Ge2+ atoms. In the second I1- site, I1- is bonded in a 1-coordinate geometry to four equivalent Cs1+ and two equivalent Ge2+ atoms.