DOI: 10.17188/1263266
title: Materials Data on Er2TiO5 by Materials Project

description: Er2TiO5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are thirteen inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded in a distorted pentagonal bipyramidal geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.19–2.42 Å. In the second Er3+ site, Er3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Er–O bond distances ranging from 2.21–2.39 Å. In the third Er3+ site, Er3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Er–O bond distances ranging from 2.12–2.37 Å. In the fourth Er3+ site, Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.21–2.68 Å. In the fifth Er3+ site, Er3+ is bonded to seven O2- atoms to form distorted ErO7 pentagonal bipyramids that share a cornercorner with one TiO6 octahedra and edges with two equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Er–O bond distances ranging from 2.13–2.42 Å. In the sixth Er3+ site, Er3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Er–O bond distances ranging from 2.13–2.45 Å. In the seventh Er3+ site, Er3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Er–O bond distances ranging from 2.12–2.71 Å. In the eighth Er3+ site, Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.19–2.63 Å. In the ninth Er3+ site, Er3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Er–O bond distances ranging from 2.14–2.52 Å. In the tenth Er3+ site, Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.19–2.56 Å. In the eleventh Er3+ site, Er3+ is bonded to seven O2- atoms to form distorted ErO7 pentagonal bipyramids that share a cornercorner with one ErO7 hexagonal pyramid, corners with two equivalent TiO6 octahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Er–O bond distances ranging from 2.19–2.56 Å. In the twelfth Er3+ site, Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.20–2.65 Å. In the thirteenth Er3+ site, Er3+ is bonded to seven O2- atoms to form distorted ErO7 hexagonal pyramids that share corners with two equivalent TiO6 octahedra, a cornercorner with one ErO7 pentagonal bipyramid, and edges with four TiO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Er–O bond distances ranging from 2.16–2.44 Å. There are five inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded in a 5-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.85–2.56 Å. 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 1.85–2.32 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with five TiO6 octahedra, a cornercorner with one ErO7 pentagonal bipyramid, and edges with two equivalent ErO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 47–51°. There are a spread of Ti–O bond distances ranging from 1.92–2.13 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one ErO7 hexagonal pyramid, corners with five TiO6 octahedra, a cornercorner with one ErO7 pentagonal bipyramid, an edgeedge with one ErO7 hexagonal pyramid, and an edgeedge with one ErO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 29–59°. There are a spread of Ti–O bond distances ranging from 1.87–2.23 Å. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three TiO6 octahedra and edges with two equivalent ErO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 47–59°. There are a spread of Ti–O bond distances ranging from 1.85–2.28 Å. There are twenty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two Er3+ and two equivalent Ti4+ atoms to form distorted corner-sharing OEr2Ti2 tetrahedra. In the second O2- site, O2- is bonded to three Er3+ and one Ti4+ atom to form distorted OEr3Ti tetrahedra that share corners with eight OEr2Ti2 tetrahedra and edges with two OEr4 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Er3+ and one Ti4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Er3+ and one Ti4+ atom. In the fifth O2- site, O2- is bonded to four Er3+ atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the sixth O2- site, O2- is bonded to two Er3+ and two equivalent Ti4+ atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the seventh O2- site, O2- is bonded to three Er3+ and one Ti4+ atom to form distorted OEr3Ti tetrahedra that share corners with seven OEr3Ti tetrahedra, a cornercorner with one OEr2Ti2 trigonal pyramid, and an edgeedge with one OEr4 tetrahedra. In the eighth O2- site, O2- is bonded to four Er3+ atoms to form OEr4 tetrahedra that share corners with twelve OEr4 tetrahedra and an edgeedge with one OEr2Ti2 tetrahedra. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Er3+ and one Ti4+ atom. In the tenth O2- site, O2- is bonded to four Er3+ atoms to form OEr4 tetrahedra that share corners with nine OEr2Ti2 tetrahedra and an edgeedge with one OEr4 tetrahedra. In the eleventh O2- site, O2- is bonded to three Er3+ and one Ti4+ atom to form distorted OEr3Ti tetrahedra that share corners with eight OEr3Ti tetrahedra and edges with two OEr4 tetrahedra. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Er3+ and two Ti4+ atoms. In the thirteenth O2- site, O2- is bonded to four Er3+ atoms to form OEr4 tetrahedra that share corners with five OEr3Ti tetrahedra and edges with five OEr4 tetrahedra. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Er3+ and two Ti4+ atoms. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Er3+ and two equivalent Ti4+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Er3+ and two equivalent Ti4+ atoms. In the seventeenth O2- site, O2- is bonded to three Er3+ and one Ti4+ atom to form corner-sharing OEr3Ti tetrahedra. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Er3+ and one Ti4+ atom. In the nineteenth O2- site, O2- is bonded to four Er3+ atoms to form distorted OEr4 tetrahedra that share corners with four OEr4 tetrahedra, corners with four equivalent OEr2Ti2 trigonal pyramids, and an edgeedge with one OEr3Ti tetrahedra. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Er3+ and two Ti4+ atoms. In the twenty-first O2- site, O2- is bonded to four Er3+ atoms to form OEr4 tetrahedra that share corners with nine OEr3Ti tetrahedra and an edgeedge with one OEr4 tetrahedra. In the twenty-second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Er3+ and two Ti4+ atoms. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to three Er3+ and one Ti4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Er3+ and two equivalent Ti4+ atoms. In the twenty-fifth O2- site, O2- is bonded to three Er3+ and one Ti4+ atom to form OEr3Ti tetrahedra that share corners with three OEr4 tetrahedra, an edgeedge with one OEr4 tetrahedra, and edges with two equivalent OEr2Ti2 trigonal pyramids. In the twenty-sixth O2- site, O2- is bonded to two Er3+ and two Ti4+ atoms to form distorted OEr2Ti2 trigonal pyramids that share corners with three OEr4 tetrahedra, corners with two equivalent OEr2Ti2 trigonal pyramids, and edges with two OEr3Ti tetrahedra. In the twenty-seventh O2- site, O2- is bonded to four Er3+ atoms to form OEr4 tetrahedra that share corners with six OEr4 tetrahedra and edges with two equivalent OEr2Ti2 trigonal pyramids. In the twenty-eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Er3+ and two equivalent Ti4+ atoms.