Materials Data on Sr2HfO4 by Materials Project

Abstract

Sr2HfO4 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.87 Å. Hf4+ is bonded to six O2- atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedral tilt angles are 23°. There are four shorter (2.07 Å) and two longer (2.12 Å) Hf–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to five equivalent Sr2+ and one Hf4+ atom to form a mixture of distorted edge and corner-sharing OSr5Hf octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two equivalent Hf4+ atoms.