Materials Data on Er2TiO5 by Materials Project

Abstract

Er2TiO5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Er3+ is bonded to six O2- atoms to form distorted ErO6 pentagonal pyramids that share a cornercorner with one TiO6 octahedra, corners with three equivalent ErO6 pentagonal pyramids, edges with three equivalent TiO6 octahedra, and edges with three equivalent ErO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 30°. There are a spread of Er–O bond distances ranging from 2.17–2.36 Å. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent ErO6 pentagonal pyramids, and edges with six equivalent ErO6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 33°. There are a spread of Ti–O bond distances ranging from 1.88–2.12 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Er3+ and one Ti4+ atom. In the second O2- site, O2- is bonded to three equivalent Er3+ and one Ti4+ atom to form distorted OEr3Ti trigonal pyramids that share a cornercorner with one OEr2Ti2 tetrahedra, corners with three equivalent OEr3Ti trigonal pyramids, edges with two equivalent OEr2Ti2 tetrahedra, and edges with two equivalent OEr3Ti trigonal pyramids. In the third O2- site, O2- is bonded to two equivalent Er3+ and two equivalent Ti4+ atoms to form distorted OEr2Ti2 tetrahedra that share corners with two equivalent OEr2Ti2 tetrahedra, corners with two equivalent OEr3Ti trigonal pyramids, and edges with four equivalent OEr3Ti trigonal pyramids.