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DOE OSTI · 1705528

Materials Data on CaHfN2 by Materials Project

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Abstract

CaHfN2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Ca2+ is bonded to six equivalent N3- atoms to form CaN6 octahedra that share corners with six equivalent HfN6 octahedra, edges with six equivalent CaN6 octahedra, and edges with six equivalent HfN6 octahedra. The corner-sharing octahedral tilt angles are 8°. All Ca–N bond lengths are 2.49 Å. Hf4+ is bonded to six equivalent N3- atoms to form HfN6 octahedra that share corners with six equivalent CaN6 octahedra, edges with six equivalent CaN6 octahedra, and edges with six equivalent HfN6 octahedra. The corner-sharing octahedral tilt angles are 8°. All Hf–N bond lengths are 2.24 Å. N3- is bonded to three equivalent Ca2+ and three equivalent Hf4+ atoms to form a mixture of edge and corner-sharing NCa3Hf3 octahedra. The corner-sharing octahedral tilt angles are 0°.

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36 MATERIALS SCIENCECa-Hf-NCaHfN2crystal structure

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2020-05-02. Materials Data on CaHfN2 by Materials Project. https://doi.org/10.17188/1705528

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