Materials Data on Er2O3 by Materials Project

Abstract

Er2O3 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.18–2.56 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Er3+ atoms to form OEr4 tetrahedra that share corners with six equivalent OEr6 octahedra, corners with six equivalent OEr4 tetrahedra, edges with three equivalent OEr6 octahedra, and edges with three equivalent OEr4 tetrahedra. The corner-sharing octahedra tilt angles range from 19–55°. In the second O2- site, O2- is bonded to six equivalent Er3+ atoms to form OEr6 octahedra that share corners with twelve equivalent OEr4 tetrahedra, edges with six equivalent OEr6 octahedra, and edges with six equivalent OEr4 tetrahedra.