Materials Data on ErGaO3 by Materials Project
ErGaO3 crystallizes in the hexagonal P6_3cm space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.25–2.49 Å. In the second Er3+ site, Er3+ is bonded to seven O2- atoms to form distorted ErO7 pentagonal bipyramids that share corners with three equivalent GaO5 trigonal bipyramids and edges with three equivalent GaO5 trigonal bipyramids. There are a spread of Er–O bond distances ranging from 2.27–2.37 Å. Ga3+ is bonded to five O2- atoms to form GaO5 trigonal bipyramids that share a cornercorner with one ErO7 pentagonal bipyramid, corners with six equivalent GaO5 trigonal bipyramids, and an edgeedge with one ErO7 pentagonal bipyramid. There are a spread of Ga–O bond distances ranging from 1.90–2.05 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Er3+ and one Ga3+ atom to form OEr3Ga tetrahedra that share corners with ten OEr3Ga tetrahedra, corners with two equivalent OErGa3 trigonal pyramids, edges with three equivalent OEr3Ga tetrahedra, and edges with two equivalent OErGa3 trigonal pyramids. In the second O2- site, O2- is bonded to three Er3+ and one Ga3+ atom to form distorted OEr3Ga tetrahedra that share corners with ten OEr3Ga tetrahedra, corners with four equivalent OErGa3 trigonal pyramids, edges with three equivalent OEr3Ga tetrahedra, and an edgeedge with one OErGa3 trigonal pyramid. In the third O2- site, O2- is bonded to one Er3+ and three equivalent Ga3+ atoms to form OErGa3 trigonal pyramids that share corners with six equivalent OEr3Ga tetrahedra, corners with six equivalent OErGa3 trigonal pyramids, and edges with three equivalent OEr3Ga tetrahedra. In the fourth O2- site, O2- is bonded to one Er3+ and three equivalent Ga3+ atoms to form distorted OErGa3 trigonal pyramids that share corners with six equivalent OEr3Ga tetrahedra, corners with six OErGa3 trigonal pyramids, and edges with three equivalent OEr3Ga tetrahedra.