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DOE OSTI · 1749377

Materials Data on Tc4N3 by Materials Project

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Abstract

Tc4N3 is MAX Phase-derived structured and crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three Tc4N3 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Tc+2.25+ sites. In the first Tc+2.25+ site, Tc+2.25+ is bonded to six N3- atoms to form a mixture of edge and corner-sharing TcN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.17 Å) and three longer (2.20 Å) Tc–N bond lengths. In the second Tc+2.25+ site, Tc+2.25+ is bonded in a 3-coordinate geometry to three equivalent N3- atoms. All Tc–N bond lengths are 2.15 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to six Tc+2.25+ atoms to form a mixture of edge and corner-sharing NTc6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second N3- site, N3- is bonded to six equivalent Tc+2.25+ atoms to form a mixture of distorted edge and corner-sharing NTc6 octahedra. The corner-sharing octahedral tilt angles are 1°.

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36 MATERIALS SCIENCEcrystal structureN-TcTc4N3

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2020-05-02. Materials Data on Tc4N3 by Materials Project. https://doi.org/10.17188/1749377

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