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DOE OSTI · 1758271

Materials Data on Y2Ti2O7 by Materials Project

Abstract

Y2Ti2O7 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are six inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.20–2.48 Å. In the second Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.21–2.44 Å. In the third Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.26–2.47 Å. In the fourth Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.17–2.72 Å. In the fifth Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.15–2.37 Å. In the sixth Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.37–2.72 Å. There are six inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.79 Å) and two longer (1.96 Å) Ti–O bond length. In the second Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.81–2.45 Å. In the third Ti4+ site, Ti4+ is bonded in a tetrahedral geometry to four O2- atoms. There is one shorter (1.82 Å) and three longer (1.83 Å) Ti–O bond length. In the fourth Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.83–2.24 Å. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.83–2.17 Å. In the sixth Ti4+ site, Ti4+ is bonded to four O2- atoms to form distorted corner-sharing TiO4 trigonal pyramids. The corner-sharing octahedral tilt angles are 32°. There is two shorter (1.83 Å) and two longer (1.86 Å) Ti–O bond length. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to two Y3+ and two Ti4+ atoms to form distorted OY2Ti2 tetrahedra that share corners with three OY2Ti2 tetrahedra and edges with two OY3Ti tetrahedra. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Y3+ and one Ti4+ atom. In the fourth O2- site, O2- is bonded to three Y3+ and one Ti4+ atom to form distorted OY3Ti tetrahedra that share corners with three OY3Ti tetrahedra and an edgeedge with one OY2Ti2 tetrahedra. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Y3+ and one Ti4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two Ti4+ atoms. In the eighth O2- site, O2- is bonded to two Y3+ and two Ti4+ atoms to form a mixture of distorted corner and edge-sharing OY2Ti2 tetrahedra. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Y3+ and two Ti4+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ti4+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and two Ti4+ atoms.

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2020-09-03. Materials Data on Y2Ti2O7 by Materials Project. https://doi.org/10.17188/1758271

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