Materials Data on Tm2TiO5 by Materials Project

Abstract

Tm2TiO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to six O2- atoms to form distorted TmO6 octahedra that share corners with two equivalent TmO6 octahedra, corners with four equivalent TiO6 octahedra, and edges with six TmO6 octahedra. The corner-sharing octahedra tilt angles range from 58–66°. There are a spread of Tm–O bond distances ranging from 2.26–2.29 Å. In the second Tm3+ site, Tm3+ is bonded to six O2- atoms to form TmO6 octahedra that share corners with four TmO6 octahedra, corners with four equivalent TiO6 octahedra, and edges with four TmO6 octahedra. The corner-sharing octahedra tilt angles range from 51–64°. There are a spread of Tm–O bond distances ranging from 2.18–2.31 Å. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with eight TmO6 octahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 34–66°. There are a spread of Ti–O bond distances ranging from 1.85–2.36 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Tm3+ atoms to form OTm4 tetrahedra that share corners with ten OTm4 tetrahedra and edges with three OTm3Ti tetrahedra. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three equivalent Ti4+ atoms. In the third O2- site, O2- is bonded to three Tm3+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OTm3Ti tetrahedra. In the fourth O2- site, O2- is bonded to three equivalent Tm3+ and one Ti4+ atom to form a mixture of edge and corner-sharing OTm3Ti tetrahedra. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Tm3+ and one Ti4+ atom.