Materials Data on Ca3GeO4F by Materials Project

Abstract

Ca3GeO4F crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to four O2- and two equivalent F1- atoms. There are one shorter (2.35 Å) and three longer (2.38 Å) Ca–O bond lengths. There are one shorter (2.40 Å) and one longer (2.72 Å) Ca–F bond lengths. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to four O2- and two equivalent F1- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.39 Å. There are one shorter (2.48 Å) and one longer (2.56 Å) Ca–F bond lengths. Ge3+ is bonded in a tetrahedral geometry to four O2- atoms. There is three shorter (1.91 Å) and one longer (1.94 Å) Ge–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three Ca2+ and one Ge3+ atom to form corner-sharing OCa3Ge tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Ge3+ atom. In the third O2- site, O2- is bonded to three Ca2+ and one Ge3+ atom to form distorted corner-sharing OCa3Ge trigonal pyramids. F1- is bonded in a 6-coordinate geometry to six Ca2+ atoms.