Materials Data on Gd2TiO5 by Materials Project

Abstract

Gd2TiO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded to seven O2- atoms to form distorted GdO7 hexagonal pyramids that share corners with two equivalent GdO7 pentagonal bipyramids, a cornercorner with one TiO5 trigonal bipyramid, edges with four equivalent GdO7 hexagonal pyramids, edges with three equivalent GdO7 pentagonal bipyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are two shorter (2.38 Å) and five longer (2.40 Å) Gd–O bond lengths. In the second Gd3+ site, Gd3+ is bonded to seven O2- atoms to form distorted GdO7 pentagonal bipyramids that share corners with two equivalent GdO7 hexagonal pyramids, corners with three equivalent TiO5 trigonal bipyramids, edges with three equivalent GdO7 hexagonal pyramids, edges with two equivalent GdO7 pentagonal bipyramids, and edges with two equivalent TiO5 trigonal bipyramids. There are a spread of Gd–O bond distances ranging from 2.32–2.44 Å. Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share a cornercorner with one GdO7 hexagonal pyramid, corners with three equivalent GdO7 pentagonal bipyramids, corners with two equivalent TiO5 trigonal bipyramids, edges with two equivalent GdO7 hexagonal pyramids, and edges with two equivalent GdO7 pentagonal bipyramids. There are a spread of Ti–O bond distances ranging from 1.79–1.98 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to three Gd3+ and one Ti4+ atom to form OGd3Ti tetrahedra that share corners with nine OGd3Ti tetrahedra and edges with four OGd2Ti2 tetrahedra. In the second O2- site, O2- is bonded to three Gd3+ and one Ti4+ atom to form distorted OGd3Ti tetrahedra that share corners with nine OGd3Ti tetrahedra and edges with five OGd2Ti2 tetrahedra. In the third O2- site, O2- is bonded to four Gd3+ atoms to form OGd4 tetrahedra that share corners with fourteen OGd3Ti tetrahedra and edges with four OGd2Ti2 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Gd3+ and one Ti4+ atom. In the fifth O2- site, O2- is bonded to two Gd3+ and two equivalent Ti4+ atoms to form a mixture of distorted corner and edge-sharing OGd2Ti2 tetrahedra.