DOI: 10.17188/1284266
title: Materials Data on Y2Ti2O7 by Materials Project

description: Y2Ti2O7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight 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 2.16–2.71 Å. In the second Y3+ site, Y3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.26–2.63 Å. In the third 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 2.18–2.76 Å. In the fourth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one TiO6 octahedra, a cornercorner with one TiO5 trigonal bipyramid, a cornercorner with one TiO4 trigonal pyramid, an edgeedge with one TiO6 octahedra, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 46°. There are a spread of Y–O bond distances ranging from 2.24–2.72 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 2.20–2.30 Å. In the sixth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one TiO6 octahedra, corners with two equivalent TiO5 trigonal bipyramids, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 15°. There are a spread of Y–O bond distances ranging from 2.14–2.42 Å. In the seventh 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 2.16–2.70 Å. In the eighth 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 2.23–2.54 Å. There are eight inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 trigonal pyramids that share a cornercorner with one YO7 pentagonal bipyramid. There are a spread of Ti–O bond distances ranging from 1.85–1.92 Å. In the second Ti4+ site, Ti4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ti–O bond distances ranging from 1.83–2.09 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two YO7 pentagonal bipyramids, a cornercorner with one TiO5 trigonal bipyramid, and an edgeedge with one YO7 pentagonal bipyramid. There are a spread of Ti–O bond distances ranging from 1.80–2.33 Å. In the fourth Ti4+ site, Ti4+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Ti–O bond distances ranging from 1.80–2.60 Å. In the fifth Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted corner-sharing TiO5 trigonal bipyramids. There are a spread of Ti–O bond distances ranging from 1.88–1.94 Å. In the sixth Ti4+ site, Ti4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ti–O bond distances ranging from 1.73–2.42 Å. In the seventh 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 1.80–2.48 Å. In the eighth Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share a cornercorner with one TiO6 octahedra, corners with three YO7 pentagonal bipyramids, and a cornercorner with one TiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 46°. There are a spread of Ti–O bond distances ranging from 1.77–2.10 Å. There are twenty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Ti4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Y3+ and one Ti4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar 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 OY3Ti tetrahedra that share corners with three OY2Ti2 tetrahedra and corners with two equivalent OY3Ti trigonal pyramids. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Y3+ and three Ti4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Ti4+ atom. In the seventh O2- site, O2- is bonded to two Y3+ and two Ti4+ atoms to form distorted corner-sharing OY2Ti2 tetrahedra. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Ti4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ti4+ atoms. In the tenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and two Ti4+ atoms. 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 to three Y3+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OY3Ti tetrahedra. In the thirteenth O2- site, O2- is bonded to three Y3+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OY3Ti trigonal pyramids. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Y3+ and one Ti4+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ti4+ atoms. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Y3+ and one Ti4+ atom. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to two Y3+ and two Ti4+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Y3+ and one Ti4+ atom. In the nineteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Y3+ and one Ti4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ti4+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and two Ti4+ atoms. In the twenty-second O2- site, O2- is bonded in a 1-coordinate geometry to two Y3+ and two Ti4+ atoms. In the twenty-third O2- site, O2- is bonded in a 1-coordinate geometry to two Y3+ and one Ti4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Y3+ and two Ti4+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Y3+ and two Ti4+ atoms. In the twenty-sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two Ti4+ atoms. In the twenty-seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Y3+ and one Ti4+ atom. In the twenty-eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Y3+ and one Ti4+ atom.