Materials Data on MgGaBO4 by Materials Project

Abstract

GaMgBO4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with three equivalent GaO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with two equivalent GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Mg–O bond distances ranging from 2.01–2.19 Å. Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with three equivalent MgO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with four equivalent GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Ga–O bond distances ranging from 1.98–2.15 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.34–1.42 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and three equivalent Ga3+ atoms to form OMgGa3 tetrahedra that share corners with seven OMg2GaB tetrahedra and edges with two equivalent OMgGa3 tetrahedra. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Mg2+ and one B3+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+, two equivalent Ga3+, and one B3+ atom. In the fourth O2- site, O2- is bonded to two equivalent Mg2+, one Ga3+, and one B3+ atom to form distorted corner-sharing OMg2GaB tetrahedra.