Hf4C3N is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form HfC6 octahedra that share corners with three equivalent Hf(2)C3N3 octahedra, corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(2)C3N3 octahedra, and edges with nine equivalent Hf(1)C6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Hf site, Hf(2) is bonded to three equivalent C(1) and three equivalent N(1) atoms to form HfC3N3 octahedra that share corners with three equivalent Hf(2)C3N3 octahedra, corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(1)C6 octahedra, and edges with nine equivalent Hf(2)C3N3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are two inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Hf(1) and three equivalent Hf(2) atoms to form CHf6 octahedra that share corners with three equivalent C(2)Hf6 octahedra, corners with three equivalent N(1)Hf6 octahedra, edges with three equivalent C(2)Hf6 octahedra, edges with three equivalent N(1)Hf6 octahedra, and edges with six equivalent C(1)Hf6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the second C site, C(2) is bonded to six equivalent Hf(1) atoms to form a mixture of edge and corner-sharing CHf6 octahedra. The corner-sharing octahedral tilt angles are 2°. N(1) is bonded to six equivalent Hf(2) atoms to form NHf6 octahedra that share corners with six equivalent C(1)Hf6 octahedra, edges with six equivalent C(1)Hf6 octahedra, and edges with six equivalent N(1)Hf6 octahedra. The corner-sharing octahedral tilt angles are 3°.
Hf4C3N is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form HfC6 octahedra that share corners with three equivalent Hf(2)C3N3 octahedra, corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(2)C3N3 octahedra, and edges with nine equivalent Hf(1)C6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. All Hf(1)-C(1) bond lengths are 2.35 Å. All Hf(1)-C(2) bond lengths are 2.29 Å. In the second Hf site, Hf(2) is bonded to three equivalent C(1) and three equivalent N(1) atoms to form HfC3N3 octahedra that share corners with three equivalent Hf(2)C3N3 octahedra, corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(1)C6 octahedra, and edges with nine equivalent Hf(2)C3N3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. All Hf(2)-C(1) bond lengths are 2.25 Å. All Hf(2)-N(1) bond lengths are 2.33 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Hf(1) and three equivalent Hf(2) atoms to form CHf6 octahedra that share corners with three equivalent C(2)Hf6 octahedra, corners with three equivalent N(1)Hf6 octahedra, edges with three equivalent C(2)Hf6 octahedra, edges with three equivalent N(1)Hf6 octahedra, and edges with six equivalent C(1)Hf6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the second C site, C(2) is bonded to six equivalent Hf(1) atoms to form a mixture of edge and corner-sharing CHf6 octahedra. The corner-sharing octahedral tilt angles are 2°. N(1) is bonded to six equivalent Hf(2) atoms to form NHf6 octahedra that share corners with six equivalent C(1)Hf6 octahedra, edges with six equivalent C(1)Hf6 octahedra, and edges with six equivalent N(1)Hf6 octahedra. The corner-sharing octahedral tilt angles are 3°.