Materials Data on ZrNb3C4 by Materials Project

Abstract

ZrNb3C4 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Zr4+ is bonded to six equivalent C4- atoms to form ZrC6 octahedra that share corners with six equivalent NbC6 octahedra, edges with six equivalent ZrC6 octahedra, and edges with six equivalent NbC6 octahedra. The corner-sharing octahedral tilt angles are 2°. All Zr–C bond lengths are 2.33 Å. There are two inequivalent Nb4+ sites. In the first Nb4+ site, Nb4+ is bonded to six C4- atoms to form NbC6 octahedra that share corners with three equivalent ZrC6 octahedra, corners with three equivalent NbC6 octahedra, edges with three equivalent ZrC6 octahedra, and edges with nine NbC6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. All Nb–C bond lengths are 2.26 Å. In the second Nb4+ site, Nb4+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing NbC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Nb–C bond lengths are 2.26 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to three equivalent Zr4+ and three equivalent Nb4+ atoms to form a mixture of corner and edge-sharing CZr3Nb3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to six Nb4+ atoms to form a mixture of corner and edge-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 0°.