Materials Data on Hf4C3N by Materials Project

Abstract

Hf4C3N is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded to six C atoms to form a mixture of edge and corner-sharing HfC6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are three shorter (2.30 Å) and three longer (2.35 Å) Hf–C bond lengths. In the second Hf site, Hf is bonded to three equivalent C and three equivalent N atoms to form a mixture of edge and corner-sharing HfC3N3 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. All Hf–C bond lengths are 2.26 Å. All Hf–N bond lengths are 2.34 Å. There are two inequivalent C sites. In the first C site, C is bonded to six Hf atoms to form CHf6 octahedra that share corners with three equivalent CHf6 octahedra, corners with three equivalent NHf6 octahedra, edges with three equivalent NHf6 octahedra, and edges with nine CHf6 octahedra. The corner-sharing octahedra tilt angles range from 2–3°. In the second C site, C is bonded to six equivalent Hf atoms to form a mixture of edge and corner-sharing CHf6 octahedra. The corner-sharing octahedral tilt angles are 2°. N is bonded to six equivalent Hf atoms to form NHf6 octahedra that share corners with six equivalent CHf6 octahedra, edges with six equivalent CHf6 octahedra, and edges with six equivalent NHf6 octahedra. The corner-sharing octahedral tilt angles are 3°.