Materials Data on SrGe(PO4)2 by Materials Project

Abstract

SrGe(PO4)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.63–3.06 Å. Ge4+ is bonded to six O2- atoms to form GeO6 octahedra that share corners with six equivalent PO4 tetrahedra. There is two shorter (1.85 Å) and four longer (1.92 Å) Ge–O bond length. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent GeO6 octahedra. The corner-sharing octahedra tilt angles range from 38–46°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ge4+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Sr2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Ge4+, and one P5+ atom.