Materials Data on Gd2Zr2O7 by Materials Project

Abstract

Gd2Zr2O7 crystallizes in the orthorhombic Pmna space group. The structure is three-dimensional. there are three inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded to six O2- atoms to form distorted GdO6 octahedra that share corners with six ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 62–66°. There are two shorter (2.26 Å) and four longer (2.31 Å) Gd–O bond lengths. In the second Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Gd–O bond distances ranging from 2.40–2.74 Å. In the third Gd3+ site, Gd3+ is bonded to eight O2- atoms to form distorted GdO8 hexagonal bipyramids that share edges with six ZrO6 octahedra. There are a spread of Gd–O bond distances ranging from 2.28–2.58 Å. There are three inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with two equivalent GdO6 octahedra, corners with four ZrO6 octahedra, and edges with two equivalent GdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 49–66°. There are a spread of Zr–O bond distances ranging from 2.07–2.16 Å. In the second Zr4+ site, Zr4+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.17–2.61 Å. In the third Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with two equivalent GdO6 octahedra, corners with four equivalent ZrO6 octahedra, and edges with two equivalent GdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 50–62°. There are four shorter (2.10 Å) and two longer (2.15 Å) Zr–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two Gd3+ and two Zr4+ atoms to form a mixture of corner and edge-sharing OGd2Zr2 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Gd3+ and two Zr4+ atoms. In the third O2- site, O2- is bonded to three Gd3+ and one Zr4+ atom to form a mixture of corner and edge-sharing OGd3Zr tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Gd3+ and three Zr4+ atoms. In the fifth O2- site, O2- is bonded to three Gd3+ and one Zr4+ atom to form a mixture of corner and edge-sharing OGd3Zr tetrahedra.