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DOE OSTI · 1288542

Materials Data on Ca2HfO4 by Materials Project

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Abstract

Ca2HfO4 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.86 Å. Hf4+ is bonded to six O2- atoms to form edge-sharing HfO6 octahedra. There are two shorter (2.07 Å) and four longer (2.14 Å) Hf–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ca2+ and one Hf4+ atom to form a mixture of distorted corner and edge-sharing OCa4Hf trigonal bipyramids. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Ca2+ and two equivalent Hf4+ atoms.

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36 MATERIALS SCIENCECa-Hf-OCa2HfO4crystal structure

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2020-07-20. Materials Data on Ca2HfO4 by Materials Project. https://doi.org/10.17188/1288542

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