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DOE OSTI · 1318546

Materials Data on MgTi2O4 by Materials Project

Abstract

MgTi2O4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 square pyramids that share corners with six TiO6 octahedra, edges with three TiO6 octahedra, edges with two equivalent MgO5 square pyramids, and a faceface with one TiO6 octahedra. The corner-sharing octahedra tilt angles range from 12–57°. There are a spread of Mg–O bond distances ranging from 2.09–2.13 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 square pyramids that share corners with six TiO6 octahedra, edges with three TiO6 octahedra, edges with two equivalent MgO5 square pyramids, and a faceface with one TiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–56°. There are a spread of Mg–O bond distances ranging from 2.08–2.14 Å. There are four inequivalent Ti3+ sites. In the first Ti3+ site, Ti3+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with four TiO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with four TiO6 octahedra, and edges with three MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Ti–O bond distances ranging from 1.89–2.36 Å. In the second Ti3+ site, Ti3+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four TiO6 octahedra, corners with four MgO5 square pyramids, edges with four TiO6 octahedra, and a faceface with one MgO5 square pyramid. The corner-sharing octahedral tilt angles are 48°. There are a spread of Ti–O bond distances ranging from 2.00–2.20 Å. In the third Ti3+ site, Ti3+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four TiO6 octahedra, corners with four MgO5 square pyramids, edges with four TiO6 octahedra, and a faceface with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 47–49°. There are a spread of Ti–O bond distances ranging from 2.00–2.20 Å. In the fourth Ti3+ site, Ti3+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with four TiO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with four TiO6 octahedra, and edges with three MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 47–48°. There are a spread of Ti–O bond distances ranging from 1.89–2.34 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and three Ti3+ atoms to form distorted OMgTi3 trigonal pyramids that share corners with two equivalent OMg2Ti3 square pyramids, a cornercorner with one OMg2Ti3 trigonal bipyramid, corners with two equivalent OMgTi3 trigonal pyramids, edges with three OMg2Ti3 square pyramids, and edges with two equivalent OMg2Ti3 trigonal bipyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti3+ atoms. In the fourth O2- site, O2- is bonded to one Mg2+ and three Ti3+ atoms to form distorted OMgTi3 trigonal pyramids that share corners with two equivalent OMg2Ti3 square pyramids, a cornercorner with one OMg2Ti3 trigonal bipyramid, corners with two equivalent OMgTi3 trigonal pyramids, edges with three OMg2Ti3 square pyramids, and edges with two equivalent OMg2Ti3 trigonal bipyramids. In the fifth O2- site, O2- is bonded to two equivalent Mg2+ and three Ti3+ atoms to form OMg2Ti3 square pyramids that share corners with two equivalent OMg2Ti3 trigonal bipyramids, corners with two equivalent OMgTi3 trigonal pyramids, edges with four OMg2Ti3 square pyramids, an edgeedge with one OMg2Ti3 trigonal bipyramid, and edges with three OMgTi3 trigonal pyramids. In the sixth O2- site, O2- is bonded to two equivalent Mg2+ and three Ti3+ atoms to form distorted OMg2Ti3 trigonal bipyramids that share corners with two equivalent OMg2Ti3 square pyramids, a cornercorner with one OMgTi3 trigonal pyramid, an edgeedge with one OMg2Ti3 square pyramid, edges with four OMg2Ti3 trigonal bipyramids, and edges with two equivalent OMgTi3 trigonal pyramids. In the seventh O2- site, O2- is bonded to two equivalent Mg2+ and three Ti3+ atoms to form OMg2Ti3 square pyramids that share corners with two equivalent OMg2Ti3 trigonal bipyramids, corners with two equivalent OMgTi3 trigonal pyramids, edges with four OMg2Ti3 square pyramids, an edgeedge with one OMg2Ti3 trigonal bipyramid, and edges with three OMgTi3 trigonal pyramids. In the eighth O2- site, O2- is bonded to two equivalent Mg2+ and three Ti3+ atoms to form distorted OMg2Ti3 trigonal bipyramids that share corners with two equivalent OMg2Ti3 square pyramids, a cornercorner with one OMgTi3 trigonal pyramid, an edgeedge with one OMg2Ti3 square pyramid, edges with four OMg2Ti3 trigonal bipyramids, and edges with two equivalent OMgTi3 trigonal pyramids.

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2020-05-02. Materials Data on MgTi2O4 by Materials Project. https://doi.org/10.17188/1318546

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