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DOE OSTI · 1284991

Materials Data on Al6C3N2 by Materials Project

Abstract

Al6C3N2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to three C4- and two equivalent N3- atoms to form distorted AlC3N2 trigonal bipyramids that share corners with two equivalent CAl4N trigonal bipyramids, corners with six AlC3N2 trigonal bipyramids, and edges with four equivalent AlC2N3 trigonal bipyramids. There are two shorter (1.92 Å) and one longer (2.12 Å) Al–C bond lengths. There are one shorter (1.96 Å) and one longer (2.25 Å) Al–N bond lengths. In the second Al3+ site, Al3+ is bonded in a bent 150 degrees geometry to two C4- atoms. There is one shorter (1.92 Å) and one longer (2.06 Å) Al–C bond length. In the third Al3+ site, Al3+ is bonded in a bent 120 degrees geometry to two equivalent C4- atoms. There are one shorter (2.05 Å) and one longer (2.06 Å) Al–C bond lengths. In the fourth Al3+ site, Al3+ is bonded in a see-saw-like geometry to two equivalent C4- and two equivalent N3- atoms. There are one shorter (2.09 Å) and one longer (2.14 Å) Al–C bond lengths. Both Al–N bond lengths are 1.92 Å. In the fifth Al3+ site, Al3+ is bonded to two equivalent C4- and three N3- atoms to form AlC2N3 trigonal bipyramids that share corners with two equivalent CAl4N trigonal bipyramids, corners with four equivalent AlC2N3 trigonal bipyramids, and edges with six AlC3N2 trigonal bipyramids. There are one shorter (2.06 Å) and one longer (2.10 Å) Al–C bond lengths. There are a spread of Al–N bond distances ranging from 1.96–2.05 Å. In the sixth Al3+ site, Al3+ is bonded to three C4- and two equivalent N3- atoms to form AlC3N2 trigonal bipyramids that share corners with six AlC3N2 trigonal bipyramids and edges with two equivalent AlC2N3 trigonal bipyramids. All Al–C bond lengths are 2.04 Å. There are one shorter (2.08 Å) and one longer (2.09 Å) Al–N bond lengths. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with seven CAl5 trigonal bipyramids and edges with four equivalent NAl5 trigonal bipyramids. In the second C4- site, C4- is bonded to four Al3+ and one N3- atom to form distorted CAl4N trigonal bipyramids that share corners with four AlC3N2 trigonal bipyramids and corners with five CAl5 trigonal bipyramids. The C–N bond length is 1.47 Å. In the third C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with eight CAl5 trigonal bipyramids and edges with two equivalent NAl5 trigonal bipyramids. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to five Al3+ atoms to form NAl5 trigonal bipyramids that share corners with four equivalent NAl5 trigonal bipyramids and edges with six CAl5 trigonal bipyramids. In the second N3- site, N3- is bonded in a 5-coordinate geometry to four Al3+ and one C4- atom.

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2020-07-22. Materials Data on Al6C3N2 by Materials Project. https://doi.org/10.17188/1284991

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