DOI: 10.17188/1284281
title: Materials Data on Er18Ti14O55 by Materials Project

description: Er18Ti14O55 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are fourteen inequivalent Er sites. In the first Er site, Er is bonded to six O atoms to form distorted ErO6 octahedra that share a cornercorner with one ErO6 octahedra and corners with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 51–75°. There are a spread of Er–O bond distances ranging from 2.17–2.29 Å. In the second Er site, Er is bonded to six O atoms to form distorted ErO6 octahedra that share a cornercorner with one ErO6 octahedra and corners with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 57–73°. There are a spread of Er–O bond distances ranging from 2.17–2.28 Å. In the third Er site, Er is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Er–O bond distances ranging from 2.19–2.65 Å. In the fourth Er site, Er is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Er–O bond distances ranging from 2.12–2.36 Å. In the fifth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with six ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.20–2.68 Å. In the sixth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with six ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.20–2.66 Å. In the seventh Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with three ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.18–2.61 Å. In the eighth Er site, Er is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Er–O bond distances ranging from 2.11–2.41 Å. In the ninth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with six ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.20–2.51 Å. In the tenth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with six ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.19–2.50 Å. In the eleventh Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with six ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.21–2.51 Å. In the twelfth Er site, Er is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Er–O bond distances ranging from 2.22–2.82 Å. In the thirteenth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share edges with four ErO8 hexagonal bipyramids and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.19–2.51 Å. In the fourteenth Er site, Er is bonded to eight O atoms to form distorted ErO8 hexagonal bipyramids that share an edgeedge with one ErO8 hexagonal bipyramid and edges with six TiO6 octahedra. There are a spread of Er–O bond distances ranging from 2.17–2.58 Å. There are ten inequivalent Ti sites. In the first Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with three ErO6 octahedra, corners with three TiO6 octahedra, and an edgeedge with one ErO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 37–73°. There are a spread of Ti–O bond distances ranging from 1.90–2.19 Å. In the second Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with six ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of Ti–O bond distances ranging from 1.97–2.01 Å. In the third Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share a cornercorner with one ErO6 octahedra, corners with five TiO6 octahedra, and edges with four ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–72°. There are a spread of Ti–O bond distances ranging from 1.95–2.06 Å. In the fourth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share a cornercorner with one ErO6 octahedra, corners with five TiO6 octahedra, and edges with four ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–75°. There are a spread of Ti–O bond distances ranging from 1.95–2.09 Å. In the fifth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with six ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Ti–O bond distances ranging from 1.94–2.00 Å. In the sixth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with five ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 47–51°. There are a spread of Ti–O bond distances ranging from 1.92–2.00 Å. In the seventh Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share a cornercorner with one ErO6 octahedra, corners with five TiO6 octahedra, and edges with two equivalent ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–66°. There are a spread of Ti–O bond distances ranging from 1.89–2.06 Å. In the eighth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with six ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Ti–O bond distances ranging from 1.94–2.00 Å. In the ninth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with four ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 49–50°. There are a spread of Ti–O bond distances ranging from 1.96–1.99 Å. In the tenth Ti site, Ti is bonded to six O atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and edges with six ErO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Ti–O bond distances ranging from 1.95–2.01 Å. There are thirty-nine inequivalent O sites. In the first O site, O is bonded to three Er and one Ti atom to form a mixture of corner and edge-sharing OEr3Ti tetrahedra. In the second O site, O is bonded to two Er and two equivalent Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the third O site, O is bonded to three Er and one Ti atom to form a mixture of corner and edge-sharing OEr3Ti tetrahedra. In the fourth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the fifth O site, O is bonded in a 4-coordinate geometry to two Er and two Ti atoms. In the sixth O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to two Er and two equivalent Ti atoms. In the eighth O site, O is bonded to three Er and one Ti atom to form a mixture of corner and edge-sharing OEr3Ti tetrahedra. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to two Er and two Ti atoms. In the tenth O site, O is bonded to three Er and one Ti atom to form a mixture of distorted corner and edge-sharing OEr3Ti tetrahedra. In the eleventh O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the twelfth O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the thirteenth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the fourteenth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the fifteenth O site, O is bonded to two equivalent Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with twelve OEr3Ti tetrahedra and edges with three OEr2Ti2 tetrahedra. In the sixteenth O site, O is bonded to two Er and two equivalent Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with fourteen OEr2Ti2 tetrahedra and edges with five OEr4 tetrahedra. In the seventeenth O site, O is bonded to two equivalent Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the eighteenth O site, O is bonded in a 3-coordinate geometry to one Er and two equivalent Ti atoms. In the nineteenth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the twentieth O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the twenty-first O site, O is bonded to two Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with twelve OEr3Ti tetrahedra and edges with three OEr2Ti2 tetrahedra. In the twenty-second O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the twenty-third O site, O is bonded in a 2-coordinate geometry to two Er and two Ti atoms. In the twenty-fourth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the twenty-fifth O site, O is bonded to two equivalent Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the twenty-sixth O site, O is bonded to two Er and two equivalent Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with eleven OEr2Ti2 tetrahedra and edges with five OEr4 tetrahedra. In the twenty-seventh O site, O is bonded to two equivalent Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with fourteen OEr2Ti2 tetrahedra and edges with five OEr4 tetrahedra. In the twenty-eighth O site, O is bonded to two Er and two equivalent Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the twenty-ninth O site, O is bonded to two Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with thirteen OEr2Ti2 tetrahedra and edges with five OEr4 tetrahedra. In the thirtieth O site, O is bonded to two Er and two Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the thirty-first O site, O is bonded to four Er atoms to form OEr4 tetrahedra that share corners with fifteen OEr4 tetrahedra and edges with four OEr2Ti2 tetrahedra. In the thirty-second O site, O is bonded to four Er atoms to form a mixture of corner and edge-sharing OEr4 tetrahedra. In the thirty-third O site, O is bonded to three Er and one Ti atom to form distorted OEr3Ti tetrahedra that share corners with eleven OEr3Ti tetrahedra and edges with four OEr2Ti2 tetrahedra. In the thirty-fourth O site, O is bonded to two equivalent Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with fourteen OEr2Ti2 tetrahedra and edges with three OEr4 tetrahedra. In the thirty-fifth O site, O is bonded to three Er and one Ti atom to form OEr3Ti tetrahedra that share corners with ten OEr3Ti tetrahedra and edges with five OEr4 tetrahedra. In the thirty-sixth O site, O is bonded to two Er and two equivalent Ti atoms to form a mixture of distorted corner and edge-sharing OEr2Ti2 tetrahedra. In the thirty-seventh O site, O is bonded to two Er and two Ti atoms to form distorted OEr2Ti2 tetrahedra that share corners with ten OEr4 tetrahedra and edges with four OEr2Ti2 tetrahedra. In the thirty-eighth O