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DOE OSTI · 1275460

Materials Data on Al5C3N by Materials Project

Abstract

Al5C3N is Aluminum carbonitride structured and crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. there are five inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to one C4- and three equivalent N3- atoms to form AlCN3 tetrahedra that share corners with ten AlCN3 tetrahedra and corners with three equivalent AlC4 trigonal pyramids. The Al–C bond length is 1.96 Å. All Al–N bond lengths are 2.02 Å. In the second Al3+ site, Al3+ is bonded to three equivalent C4- and one N3- atom to form AlC3N tetrahedra that share corners with twelve AlCN3 tetrahedra and edges with three equivalent AlC4 tetrahedra. All Al–C bond lengths are 2.12 Å. The Al–N bond length is 1.85 Å. In the third Al3+ site, Al3+ is bonded to four C4- atoms to form distorted AlC4 trigonal pyramids that share corners with four AlCN3 tetrahedra, corners with six equivalent AlC4 trigonal pyramids, and edges with three equivalent AlC4 tetrahedra. There are three shorter (1.93 Å) and one longer (2.26 Å) Al–C bond lengths. In the fourth Al3+ site, Al3+ is bonded to four C4- atoms to form distorted AlC4 tetrahedra that share corners with twelve AlC3N tetrahedra, a cornercorner with one AlC4 trigonal pyramid, and edges with three equivalent AlC3N tetrahedra. There are one shorter (1.90 Å) and three longer (2.19 Å) Al–C bond lengths. In the fifth Al3+ site, Al3+ is bonded to four C4- atoms to form AlC4 tetrahedra that share corners with ten AlCN3 tetrahedra and edges with three equivalent AlC4 trigonal pyramids. There are three shorter (1.95 Å) and one longer (2.15 Å) Al–C 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 three equivalent NAl4 tetrahedra, corners with six equivalent CAl5 trigonal bipyramids, and edges with three equivalent CAl5 trigonal bipyramids. In the second C4- site, C4- is bonded to five Al3+ atoms to form distorted CAl5 trigonal bipyramids that share corners with three equivalent CAl6 octahedra, corners with six equivalent CAl5 trigonal bipyramids, and edges with three equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 61°. In the third C4- site, C4- is bonded to six Al3+ atoms to form CAl6 octahedra that share corners with three equivalent NAl4 tetrahedra, corners with three equivalent CAl5 trigonal bipyramids, and edges with six equivalent CAl6 octahedra. N3- is bonded to four Al3+ atoms to form NAl4 tetrahedra that share corners with three equivalent CAl6 octahedra, corners with six equivalent NAl4 tetrahedra, and corners with three equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 64°.

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2020-07-14. Materials Data on Al5C3N by Materials Project. https://doi.org/10.17188/1275460

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