DOI: 10.17188/1273491
title: Materials Data on Y(FeO2)2 by Materials Project

description: YFe2O4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six O2- atoms to form distorted YO6 octahedra that share corners with six FeO5 trigonal bipyramids and edges with six equivalent YO6 octahedra. There are one shorter (2.29 Å) and five longer (2.30 Å) Y–O bond lengths. In the second Y3+ site, Y3+ is bonded to six equivalent O2- atoms to form YO6 octahedra that share corners with six equivalent FeO5 trigonal bipyramids and edges with six equivalent YO6 octahedra. All Y–O bond lengths are 2.30 Å. There are three inequivalent Fe+2.50+ sites. In the first Fe+2.50+ site, Fe+2.50+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with three equivalent YO6 octahedra, corners with six equivalent FeO5 trigonal bipyramids, and edges with three equivalent FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 62–63°. There are a spread of Fe–O bond distances ranging from 1.98–2.13 Å. In the second Fe+2.50+ site, Fe+2.50+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with three equivalent YO6 octahedra, corners with six equivalent FeO5 trigonal bipyramids, and edges with three equivalent FeO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 62–64°. There are a spread of Fe–O bond distances ranging from 1.98–2.14 Å. In the third Fe+2.50+ site, Fe+2.50+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with three equivalent YO6 octahedra, corners with six equivalent FeO5 trigonal bipyramids, and edges with three equivalent FeO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are a spread of Fe–O bond distances ranging from 1.98–2.13 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to four Fe+2.50+ atoms to form OFe4 trigonal pyramids that share corners with four OY3Fe tetrahedra, corners with six equivalent OFe4 trigonal pyramids, and edges with three equivalent OFe4 trigonal pyramids. In the second O2- site, O2- is bonded to three equivalent Y3+ and one Fe+2.50+ atom to form OY3Fe tetrahedra that share corners with nine OY3Fe tetrahedra, corners with four OFe4 trigonal pyramids, and edges with three equivalent OY3Fe tetrahedra. In the third O2- site, O2- is bonded to three equivalent Y3+ and one Fe+2.50+ atom to form OY3Fe tetrahedra that share corners with nine equivalent OY3Fe tetrahedra, corners with four OFe4 trigonal pyramids, and edges with three equivalent OY3Fe tetrahedra. In the fourth O2- site, O2- is bonded to four Fe+2.50+ atoms to form OFe4 trigonal pyramids that share corners with four OY3Fe tetrahedra, corners with six equivalent OFe4 trigonal pyramids, and edges with three equivalent OFe4 trigonal pyramids. In the fifth O2- site, O2- is bonded to four equivalent Fe+2.50+ atoms to form OFe4 trigonal pyramids that share corners with four equivalent OY3Fe tetrahedra, corners with six equivalent OFe4 trigonal pyramids, and edges with three equivalent OFe4 trigonal pyramids. In the sixth O2- site, O2- is bonded to three equivalent Y3+ and one Fe+2.50+ atom to form OY3Fe tetrahedra that share corners with nine OY3Fe tetrahedra, corners with four equivalent OFe4 trigonal pyramids, and edges with three equivalent OY3Fe tetrahedra.