Materials Data on Li2Hf2O5 by Materials Project

Abstract

Li2Hf2O5 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.00–2.52 Å. Hf4+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing HfO6 octahedra. The corner-sharing octahedra tilt angles range from 0–54°. There are a spread of Hf–O bond distances ranging from 2.02–2.15 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a square co-planar geometry to two equivalent Li1+ and two equivalent Hf4+ atoms. In the second O2- site, O2- is bonded to one Li1+ and three equivalent Hf4+ atoms to form distorted OLiHf3 trigonal pyramids that share a cornercorner with one OLi4Hf2 octahedra, corners with four equivalent OLiHf3 trigonal pyramids, edges with two equivalent OLi4Hf2 octahedra, and an edgeedge with one OLiHf3 trigonal pyramid. The corner-sharing octahedral tilt angles are 84°. In the third O2- site, O2- is bonded to four equivalent Li1+ and two equivalent Hf4+ atoms to form distorted OLi4Hf2 octahedra that share corners with two equivalent OLiHf3 trigonal pyramids, edges with two equivalent OLi4Hf2 octahedra, and edges with four equivalent OLiHf3 trigonal pyramids. In the fourth O2- site, O2- is bonded in a square co-planar geometry to two equivalent Li1+ and two equivalent Hf4+ atoms.