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DOE OSTI · 1679151

Materials Data on Nb4C3 by Materials Project

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Abstract

Nb4C3 is MAX Phase-derived structured and crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three Nb4C3 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Nb3+ sites. In the first Nb3+ site, Nb3+ is bonded to six C4- atoms to form a mixture of edge and corner-sharing NbC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.24 Å) and three longer (2.27 Å) Nb–C bond lengths. In the second Nb3+ site, Nb3+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Nb–C bond lengths are 2.17 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb3+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second C4- site, C4- is bonded to six equivalent Nb3+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°.

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36 MATERIALS SCIENCEC-Nbcrystal structureNb4C3

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2020-05-02. Materials Data on Nb4C3 by Materials Project. https://doi.org/10.17188/1679151

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