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Materials Data on Gd2NbGaO7 by Materials Project

Gd2NbGaO7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded to eight O2- atoms to form distorted GdO8 hexagonal bipyramids that share edges with two equivalent GdO8 hexagonal bipyramids, edges with two equivalent GaO6 octahedra, and edges with four equivalent NbO6 octahedra. There are a spread of Gd–O bond distances ranging from 2.23–2.56 Å. In the second Gd3+ site, Gd3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Gd–O bond distances ranging from 2.27–2.55 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent GaO6 octahedra, and edges with four equivalent GdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–49°. There are four shorter (2.00 Å) and two longer (2.04 Å) Nb–O bond lengths. Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with two equivalent GaO6 octahedra, corners with four equivalent NbO6 octahedra, and edges with two equivalent GdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 49–51°. There are two shorter (2.00 Å) and four longer (2.04 Å) Ga–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Gd3+ atoms to form corner-sharing OGd4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Gd3+ and two equivalent Ga3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Gd3+, one Nb5+, and one Ga3+ atom.

36 MATERIALS SCIENCE↗