Materials Data on Ce2TiO5 by Materials Project

Abstract

Ce2TiO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded to seven O2- atoms to form distorted CeO7 hexagonal pyramids that share corners with two equivalent CeO7 hexagonal pyramids, corners with three equivalent TiO5 trigonal bipyramids, edges with five CeO7 hexagonal pyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are a spread of Ce–O bond distances ranging from 2.37–2.51 Å. In the second Ce3+ site, Ce3+ is bonded to seven O2- atoms to form distorted CeO7 hexagonal pyramids that share corners with two equivalent CeO7 hexagonal pyramids, a cornercorner with one TiO5 trigonal bipyramid, edges with seven CeO7 hexagonal pyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are a spread of Ce–O bond distances ranging from 2.39–2.44 Å. Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with four CeO7 hexagonal pyramids, corners with two equivalent TiO5 trigonal bipyramids, and edges with four CeO7 hexagonal pyramids. There are a spread of Ti–O bond distances ranging from 1.83–2.01 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ce3+ atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ce3+ and one Ti4+ atom. In the third O2- site, O2- is bonded to three Ce3+ and one Ti4+ atom to form distorted OCe3Ti tetrahedra that share corners with eight OCe4 tetrahedra and edges with three OCe3Ti tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Ce3+ and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded to three Ce3+ and one Ti4+ atom to form OCe3Ti tetrahedra that share corners with eight OCe4 tetrahedra and edges with two equivalent OCe3Ti tetrahedra.