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DOE OSTI · 1700981

Materials Data on ScNbN by Materials Project

Abstract

ScNbN is MAX Phase-like structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Sc sites. In the first Sc site, Sc is bonded to six equivalent N atoms to form edge-sharing ScN6 octahedra. All Sc–N bond lengths are 2.23 Å. In the second Sc site, Sc is bonded to six equivalent Sc and six equivalent Nb atoms to form ScSc6Nb6 cuboctahedra that share corners with six equivalent ScSc6Nb6 cuboctahedra, corners with six equivalent NSc3Nb3 octahedra, edges with six equivalent ScSc6Nb6 cuboctahedra, edges with six equivalent NSc3Nb3 octahedra, and faces with six equivalent ScSc6Nb6 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. All Sc–Sc bond lengths are 3.11 Å. All Sc–Nb bond lengths are 3.13 Å. Nb is bonded in a 3-coordinate geometry to three equivalent Sc and three equivalent N atoms. All Nb–N bond lengths are 2.21 Å. N is bonded to three equivalent Sc and three equivalent Nb atoms to form NSc3Nb3 octahedra that share corners with three equivalent ScSc6Nb6 cuboctahedra, corners with three equivalent NSc3Nb3 octahedra, edges with three equivalent ScSc6Nb6 cuboctahedra, and edges with nine equivalent NSc3Nb3 octahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-05-03. Materials Data on ScNbN by Materials Project. https://doi.org/10.17188/1700981

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