Materials Data on EuGdTi2O7 by Materials Project

Abstract

GdEuTi2O7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Gd3+ is bonded to eight O2- atoms to form distorted GdO8 hexagonal bipyramids that share edges with two equivalent GdO8 hexagonal bipyramids, edges with four equivalent EuO8 hexagonal bipyramids, and edges with six TiO6 octahedra. There are a spread of Gd–O bond distances ranging from 2.22–2.55 Å. Eu3+ is bonded to eight O2- atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent EuO8 hexagonal bipyramids, edges with four equivalent GdO8 hexagonal bipyramids, and edges with six TiO6 octahedra. There are a spread of Eu–O bond distances ranging from 2.23–2.57 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra, edges with two equivalent EuO8 hexagonal bipyramids, and edges with four equivalent GdO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. There is two shorter (1.97 Å) and four longer (1.98 Å) Ti–O bond length. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra, edges with two equivalent GdO8 hexagonal bipyramids, and edges with four equivalent EuO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–47°. All Ti–O bond lengths are 1.98 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Gd3+ and two equivalent Eu3+ atoms to form corner-sharing OEu2Gd2 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu3+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Gd3+, one Eu3+, and two Ti4+ atoms.