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DOE OSTI · 1196536

Materials Data on SiAs2 by Materials Project

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Abstract

SiAs2 is Pyrite structured and crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. Si4+ is bonded to six equivalent As2- atoms to form SiAs6 octahedra that share corners with twelve equivalent SiAs6 octahedra and corners with six equivalent AsSi3As tetrahedra. The corner-sharing octahedral tilt angles are 64°. All Si–As bond lengths are 2.55 Å. As2- is bonded to three equivalent Si4+ and one As2- atom to form distorted AsSi3As tetrahedra that share corners with three equivalent SiAs6 octahedra and corners with fifteen equivalent AsSi3As tetrahedra. The corner-sharing octahedral tilt angles are 78°. The As–As bond length is 2.45 Å.

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36 MATERIALS SCIENCEAs-Sicrystal structureSiAs2

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2020-07-15. Materials Data on SiAs2 by Materials Project. https://doi.org/10.17188/1196536

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