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DOE OSTI · 1296880

Materials Data on MgTi5O10 by Materials Project

Abstract

MgTi5O10 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with two equivalent TiO6 octahedra and edges with six TiO6 octahedra. The corner-sharing octahedral tilt angles are 28°. There are a spread of Mg–O bond distances ranging from 2.02–2.17 Å. There are three inequivalent Ti+3.60+ sites. In the first Ti+3.60+ site, Ti+3.60+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three TiO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 30–49°. There are a spread of Ti–O bond distances ranging from 1.93–2.14 Å. In the second Ti+3.60+ site, Ti+3.60+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with three TiO6 octahedra, an edgeedge with one MgO6 octahedra, and edges with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 28–52°. There are a spread of Ti–O bond distances ranging from 1.83–2.19 Å. In the third Ti+3.60+ site, Ti+3.60+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.95–2.14 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+ and two Ti+3.60+ atoms. In the second O2- site, O2- is bonded to one Mg2+ and three Ti+3.60+ atoms to form a mixture of distorted edge and corner-sharing OMgTi3 trigonal pyramids. In the third O2- site, O2- is bonded to one Mg2+ and three Ti+3.60+ atoms to form distorted OMgTi3 trigonal pyramids that share corners with four OMgTi3 trigonal pyramids and edges with four OTi4 trigonal pyramids. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.60+ atoms. In the fifth O2- site, O2- is bonded to four Ti+3.60+ atoms to form a mixture of distorted edge and corner-sharing OTi4 trigonal pyramids. In the sixth O2- site, O2- is bonded to one Mg2+ and three Ti+3.60+ atoms to form distorted OMgTi3 trigonal pyramids that share corners with four OMgTi3 trigonal pyramids and edges with four OTi4 trigonal pyramids.

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2020-04-29. Materials Data on MgTi5O10 by Materials Project. https://doi.org/10.17188/1296880

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