Materials Data on SrGe2(BO4)2 by Materials Project

Abstract

SrGe2(BO4)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.64 Å. B3+ is bonded to four O2- atoms to form BO4 tetrahedra that share a cornercorner with one BO4 tetrahedra and corners with three equivalent GeO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.53 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share a cornercorner with one GeO4 tetrahedra and corners with three equivalent BO4 tetrahedra. There is two shorter (1.76 Å) and two longer (1.77 Å) Ge–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one B3+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one B3+, and one Ge4+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Ge4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two equivalent B3+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one B3+, and one Ge4+ atom.