Materials Data on CaF2 by Materials Project
CaF2 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. Ca2+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Ca–F bond distances ranging from 2.22–2.44 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted rectangular see-saw-like geometry to four equivalent Ca2+ atoms. In the second F1- site, F1- is bonded in a distorted T-shaped geometry to three equivalent Ca2+ atoms.