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DOE OSTI · 1317054

Materials Data on HfAs by Materials Project

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Abstract

HfAs is Molybdenum Carbide MAX Phase-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded to six As atoms to form a mixture of face, edge, and corner-sharing HfAs6 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. There are three shorter (2.65 Å) and three longer (2.78 Å) Hf–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded to six equivalent Hf atoms to form a mixture of distorted edge and corner-sharing AsHf6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 4°. In the second As site, As is bonded to six equivalent Hf atoms to form a mixture of edge and corner-sharing AsHf6 octahedra.

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36 MATERIALS SCIENCEAs-Hfcrystal structureHfAs

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2020-07-16. Materials Data on HfAs by Materials Project. https://doi.org/10.17188/1317054

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