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DOE OSTI · 1730747

Materials Data on GaSiC4N by Materials Project

Abstract

GaSiC4N crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded in a 3-coordinate geometry to one C1- and two N3- atoms. The Ga–C bond length is 1.90 Å. There is one shorter (1.88 Å) and one longer (1.95 Å) Ga–N bond length. In the second Ga3+ site, Ga3+ is bonded to one C1- and three N3- atoms to form GaCN3 trigonal pyramids that share a cornercorner with one SiC3N tetrahedra and an edgeedge with one GaCN3 trigonal pyramid. The Ga–C bond length is 2.01 Å. There are two shorter (1.95 Å) and one longer (2.23 Å) Ga–N bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to three C1- and one N3- atom to form distorted SiC3N tetrahedra that share a cornercorner with one GaCN3 trigonal pyramid. There are a spread of Si–C bond distances ranging from 1.85–1.93 Å. The Si–N bond length is 1.73 Å. In the second Si4+ site, Si4+ is bonded in a 4-coordinate geometry to three C1- and one N3- atom. There is one shorter (1.82 Å) and two longer (1.83 Å) Si–C bond length. The Si–N bond length is 1.71 Å. There are eight inequivalent C1- sites. In the first C1- site, C1- is bonded in a distorted trigonal planar geometry to one Ga3+, one Si4+, and one C1- atom. The C–C bond length is 1.35 Å. In the second C1- site, C1- is bonded in a 3-coordinate geometry to one Ga3+, one Si4+, and one C1- atom. The C–C bond length is 1.36 Å. In the third C1- site, C1- is bonded in a 3-coordinate geometry to one Si4+ and two C1- atoms. The C–C bond length is 1.44 Å. In the fourth C1- site, C1- is bonded in a 3-coordinate geometry to three C1- atoms. There is one shorter (1.39 Å) and one longer (1.57 Å) C–C bond length. In the fifth C1- site, C1- is bonded in a distorted T-shaped geometry to one Si4+ and two equivalent C1- atoms. In the sixth C1- site, C1- is bonded in a 1-coordinate geometry to one Si4+ and two C1- atoms. There is one shorter (1.41 Å) and one longer (1.50 Å) C–C bond length. In the seventh C1- site, C1- is bonded in a 1-coordinate geometry to one Si4+ and two C1- atoms. The C–C bond length is 1.42 Å. In the eighth C1- site, C1- is bonded in a 2-coordinate geometry to three C1- atoms. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a 3-coordinate geometry to two Ga3+ and one Si4+ atom. In the second N3- site, N3- is bonded to three Ga3+ and one Si4+ atom to form edge-sharing NGa3Si trigonal pyramids.

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2020-05-02. Materials Data on GaSiC4N by Materials Project. https://doi.org/10.17188/1730747

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36 MATERIALS SCIENCE↗