Materials Data on BaMg2V2O8 by Materials Project
BaMg2V2O8 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent MgO6 octahedra, corners with four equivalent VO4 tetrahedra, edges with four equivalent VO4 tetrahedra, faces with two equivalent BaO12 cuboctahedra, and faces with four equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ba–O bond distances ranging from 2.78–3.17 Å. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent BaO12 cuboctahedra, corners with six equivalent VO4 tetrahedra, edges with two equivalent MgO6 octahedra, and faces with two equivalent BaO12 cuboctahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.19 Å. V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent BaO12 cuboctahedra, corners with six equivalent MgO6 octahedra, and edges with two equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 45–56°. There is two shorter (1.73 Å) and two longer (1.77 Å) V–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Mg2+, and one V5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, two equivalent Mg2+, and one V5+ atom.