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DOE OSTI · 1726989

Materials Data on Mg6Te5O16 by Materials Project

Abstract

Mg6Te5O16 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent MgO5 trigonal bipyramids, and edges with two equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Mg–O bond distances ranging from 2.08–2.22 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 trigonal bipyramids that share corners with four MgO6 octahedra and an edgeedge with one MgO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 53–73°. There are a spread of Mg–O bond distances ranging from 2.05–2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent MgO5 trigonal bipyramids, and edges with three MgO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Mg–O bond distances ranging from 2.04–2.21 Å. There are four inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–2.62 Å. In the second Te4+ site, Te4+ is bonded in a 4-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–1.92 Å. In the third Te4+ site, Te4+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are two shorter (1.93 Å) and two longer (2.08 Å) Te–O bond lengths. In the fourth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is one shorter (1.88 Å) and two longer (1.93 Å) Te–O bond length. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one Te4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Te4+ atom. In the third O2- site, O2- is bonded to three Mg2+ and one Te4+ atom to form a mixture of distorted edge and corner-sharing OMg3Te tetrahedra. In the fourth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two equivalent Mg2+ and one Te4+ atom. In the fifth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Mg2+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two equivalent Mg2+ and one Te4+ atom. In the seventh O2- site, O2- is bonded in a trigonal non-coplanar geometry to two equivalent Mg2+ and one Te4+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mg2+ and two Te4+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Te4+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Te4+ atom.

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2020-04-29. Materials Data on Mg6Te5O16 by Materials Project. https://doi.org/10.17188/1726989

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36 MATERIALS SCIENCE↗