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DOE OSTI · 1322665

Materials Data on MgTi2CoO7 by Materials Project

Abstract

MgTi2CoO7 crystallizes in the monoclinic P2_1/c 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 trigonal bipyramids that share corners with three TiO4 tetrahedra, a cornercorner with one CoO5 trigonal bipyramid, corners with two equivalent TiO5 trigonal bipyramids, an edgeedge with one MgO5 square pyramid, and an edgeedge with one CoO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.06–2.14 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted MgO5 square pyramids that share corners with three equivalent TiO4 tetrahedra, a cornercorner with one TiO5 trigonal bipyramid, a cornercorner with one CoO5 trigonal bipyramid, an edgeedge with one MgO5 trigonal bipyramid, and an edgeedge with one TiO5 trigonal bipyramid. There are a spread of Mg–O bond distances ranging from 2.00–2.06 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with three equivalent MgO5 square pyramids, a cornercorner with one TiO5 trigonal bipyramid, a cornercorner with one CoO5 trigonal bipyramid, and corners with two equivalent MgO5 trigonal bipyramids. There are a spread of Ti–O bond distances ranging from 1.80–1.87 Å. In the second Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share a cornercorner with one MgO5 square pyramid, a cornercorner with one TiO4 tetrahedra, corners with two equivalent MgO5 trigonal bipyramids, corners with two equivalent CoO5 trigonal bipyramids, and an edgeedge with one TiO5 trigonal bipyramid. There are a spread of Ti–O bond distances ranging from 1.78–2.04 Å. In the third Ti4+ site, Ti4+ is bonded to five O2- atoms to form TiO5 trigonal bipyramids that share a cornercorner with one TiO4 tetrahedra, corners with four CoO5 trigonal bipyramids, an edgeedge with one MgO5 square pyramid, and an edgeedge with one TiO5 trigonal bipyramid. There are a spread of Ti–O bond distances ranging from 1.80–2.14 Å. In the fourth Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share a cornercorner with one MgO5 trigonal bipyramid, a cornercorner with one TiO5 trigonal bipyramid, and corners with four CoO5 trigonal bipyramids. There are a spread of Ti–O bond distances ranging from 1.77–1.98 Å. There are two inequivalent Co4+ sites. In the first Co4+ site, Co4+ is bonded to five O2- atoms to form distorted CoO5 trigonal bipyramids that share corners with two equivalent TiO4 tetrahedra, a cornercorner with one MgO5 trigonal bipyramid, corners with four TiO5 trigonal bipyramids, and an edgeedge with one CoO5 trigonal bipyramid. There are a spread of Co–O bond distances ranging from 1.84–2.01 Å. In the second Co4+ site, Co4+ is bonded to five O2- atoms to form CoO5 trigonal bipyramids that share a cornercorner with one MgO5 square pyramid, corners with three TiO4 tetrahedra, corners with two equivalent TiO5 trigonal bipyramids, an edgeedge with one MgO5 trigonal bipyramid, and an edgeedge with one CoO5 trigonal bipyramid. There are a spread of Co–O bond distances ranging from 1.79–1.92 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+ and one Ti4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one Ti4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Ti4+, and one Co4+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Ti4+ and one Co4+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Ti4+, and one Co4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ti4+ and two Co4+ atoms. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to one Mg2+, one Ti4+, and one Co4+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Ti4+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two Ti4+ atoms. In the tenth O2- site, O2- is bonded in a water-like geometry to two Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ti4+ and two Co4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Ti4+ atoms. In the thirteenth O2- site, O2- is bonded in a trigonal planar geometry to one Mg2+, one Ti4+, and one Co4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ti4+ and one Co4+ atom.

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2014-09-30. Materials Data on MgTi2CoO7 by Materials Project. https://doi.org/10.17188/1322665

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