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DOE OSTI · 1742017

Materials Data on HfWC2 by Materials Project

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Abstract

HfWC2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Hf4+ is bonded to six equivalent C4- atoms to form HfC6 octahedra that share corners with six equivalent WC6 octahedra, edges with six equivalent HfC6 octahedra, and edges with six equivalent WC6 octahedra. The corner-sharing octahedral tilt angles are 3°. All Hf–C bond lengths are 2.29 Å. W4+ is bonded to six equivalent C4- atoms to form WC6 octahedra that share corners with six equivalent HfC6 octahedra, edges with six equivalent HfC6 octahedra, and edges with six equivalent WC6 octahedra. The corner-sharing octahedral tilt angles are 3°. All W–C bond lengths are 2.21 Å. C4- is bonded to three equivalent Hf4+ and three equivalent W4+ atoms to form a mixture of edge and corner-sharing CHf3W3 octahedra. The corner-sharing octahedral tilt angles are 0°.

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36 MATERIALS SCIENCEC-Hf-Wcrystal structureHfWC2

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2020-05-03. Materials Data on HfWC2 by Materials Project. https://doi.org/10.17188/1742017

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