Materials Data on BaMgTe2O7 by Materials Project
BaMgTe2O7 crystallizes in the orthorhombic Ama2 space group. The structure is three-dimensional. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.83–3.06 Å. Mg2+ is bonded to five O2- atoms to form distorted MgO5 trigonal bipyramids that share corners with three equivalent TeO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. There are two inequivalent Te5+ sites. In the first Te5+ site, Te5+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with two equivalent TeO6 octahedra and corners with three equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 50°. There are a spread of Te–O bond distances ranging from 1.90–2.04 Å. In the second Te5+ site, Te5+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.88–2.34 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+ and two Te5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+, one Mg2+, and one Te5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Te5+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+, one Mg2+, and one Te5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Te5+ atoms.