Materials Data on Eu2TiO5 by Materials Project

Abstract

Eu2TiO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded to seven O2- atoms to form distorted EuO7 hexagonal pyramids that share corners with two equivalent EuO7 hexagonal pyramids, a cornercorner with one TiO5 trigonal bipyramid, edges with seven EuO7 hexagonal pyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are a spread of Eu–O bond distances ranging from 2.39–2.49 Å. In the second Eu3+ site, Eu3+ is bonded to seven O2- atoms to form distorted EuO7 hexagonal pyramids that share corners with two equivalent EuO7 hexagonal pyramids, corners with three equivalent TiO5 trigonal bipyramids, edges with five EuO7 hexagonal pyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are a spread of Eu–O bond distances ranging from 2.35–2.53 Å. Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with four EuO7 hexagonal pyramids, corners with two equivalent TiO5 trigonal bipyramids, and edges with four EuO7 hexagonal pyramids. There are a spread of Ti–O bond distances ranging from 1.78–1.98 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Eu3+ atoms to form OEu4 tetrahedra that share corners with twelve OEu4 tetrahedra and edges with three OEu3Ti tetrahedra. In the second O2- site, O2- is bonded to three Eu3+ and one Ti4+ atom to form distorted OEu3Ti tetrahedra that share corners with eight OEu4 tetrahedra and edges with three OEu3Ti tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Eu3+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded to three Eu3+ and one Ti4+ atom to form OEu3Ti tetrahedra that share corners with eight OEu4 tetrahedra and edges with two equivalent OEu3Ti tetrahedra. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Eu3+ and one Ti4+ atom.