DOI: 10.17188/1298806
title: Materials Data on Y4Ga2O9 by Materials Project

description: Y4Ga2O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.27–2.68 Å. In the second Y3+ site, Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with three equivalent GaO4 tetrahedra, corners with two equivalent GaO4 trigonal pyramids, and edges with two equivalent YO7 pentagonal bipyramids. There are a spread of Y–O bond distances ranging from 2.21–2.39 Å. In the third Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one GaO4 tetrahedra, corners with two equivalent GaO4 trigonal pyramids, edges with two equivalent YO6 octahedra, an edgeedge with one GaO4 tetrahedra, and an edgeedge with one GaO4 trigonal pyramid. There are a spread of Y–O bond distances ranging from 2.26–2.50 Å. In the fourth Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Y–O bond distances ranging from 2.27–2.73 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three equivalent YO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, a cornercorner with one GaO4 trigonal pyramid, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 57–65°. There are a spread of Ga–O bond distances ranging from 1.83–1.90 Å. In the second Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 trigonal pyramids that share corners with two equivalent YO6 octahedra, corners with two equivalent YO7 pentagonal bipyramids, a cornercorner with one GaO4 tetrahedra, and an edgeedge with one YO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 45–64°. There are a spread of Ga–O bond distances ranging from 1.84–1.89 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ga3+ atom. In the second O2- site, O2- is bonded to three Y3+ and one Ga3+ atom to form distorted OY3Ga tetrahedra that share corners with seven OY3Ga tetrahedra, a cornercorner with one OY3Ga trigonal pyramid, an edgeedge with one OY2Ga2 tetrahedra, and an edgeedge with one OY3Ga trigonal pyramid. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ga3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Y3+ and one Ga3+ atom. In the fifth O2- site, O2- is bonded to three Y3+ and one Ga3+ atom to form distorted OY3Ga tetrahedra that share corners with eight OY3Ga tetrahedra, an edgeedge with one OY2Ga2 tetrahedra, and an edgeedge with one OY3Ga trigonal pyramid. In the sixth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with eight OY3Ga tetrahedra, corners with four equivalent OY3Ga trigonal pyramids, and edges with three OY4 tetrahedra. In the seventh O2- site, O2- is bonded to two Y3+ and two Ga3+ atoms to form a mixture of distorted corner and edge-sharing OY2Ga2 tetrahedra. In the eighth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with eight OY3Ga tetrahedra, a cornercorner with one OY3Ga trigonal pyramid, edges with two OY4 tetrahedra, and an edgeedge with one OY3Ga trigonal pyramid. In the ninth O2- site, O2- is bonded to three Y3+ and one Ga3+ atom to form a mixture of distorted corner and edge-sharing OY3Ga trigonal pyramids.