Materials Data on Mg3V2O8 by Materials Project
Mg3(VO4)2 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent VO4 tetrahedra and edges with four equivalent MgO6 octahedra. There are two shorter (2.06 Å) and four longer (2.15 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent VO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.18 Å. V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with nine MgO6 octahedra. The corner-sharing octahedra tilt angles range from 50–57°. There are a spread of V–O bond distances ranging from 1.73–1.83 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one V5+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one V5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Mg2+ and one V5+ atom.