Materials Data on BaAlGaO4 by Materials Project
BaGaAlO4 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.78–3.21 Å. Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three equivalent GaO4 tetrahedra. There is one shorter (1.84 Å) and three longer (1.85 Å) Ga–O bond length. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one GaO4 tetrahedra and corners with three equivalent AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to three equivalent Ba2+, one Ga3+, and one Al3+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+ and two equivalent Ga3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Ga3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Al3+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Al3+ atoms.