Materials Data on HfMoC2 by Materials Project
HfMoC2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Hf4+ is bonded to six C4- atoms to form HfC6 octahedra that share corners with six equivalent HfC6 octahedra, edges with four equivalent HfC6 octahedra, and edges with eight equivalent MoC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.24 Å) and four longer (2.26 Å) Hf–C bond lengths. Mo4+ is bonded to six C4- atoms to form MoC6 octahedra that share corners with six equivalent MoC6 octahedra, edges with four equivalent MoC6 octahedra, and edges with eight equivalent HfC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.24 Å) and four longer (2.26 Å) Mo–C bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to two equivalent Hf4+ and four equivalent Mo4+ atoms to form a mixture of corner and edge-sharing CHf2Mo4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to four equivalent Hf4+ and two equivalent Mo4+ atoms to form CHf4Mo2 octahedra that share corners with six equivalent CHf4Mo2 octahedra and edges with twelve CHf2Mo4 octahedra. The corner-sharing octahedral tilt angles are 0°.