Materials Data on Y2HfO5 by Materials Project

Abstract

Y2HfO5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.29–2.86 Å. In the second 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 2.27–2.50 Å. Hf4+ is bonded to five O2- atoms to form distorted corner-sharing HfO5 trigonal bipyramids. There are a spread of Hf–O bond distances ranging from 1.98–2.13 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Y3+ and two equivalent Hf4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Y3+ and one Hf4+ atom. In the third O2- site, O2- is bonded to three Y3+ and one Hf4+ atom to form distorted OY3Hf tetrahedra that share corners with three OY3Hf tetrahedra and edges with two equivalent OY4 tetrahedra. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with five OY3Hf tetrahedra and edges with three OY4 tetrahedra. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Y3+ and one Hf4+ atom.