Materials Data on CoMo by Materials Project

Abstract

CoMo is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are seven inequivalent Mo sites. In the first Mo site, Mo is bonded in a 6-coordinate geometry to four Mo and twelve Co atoms. There are one shorter (2.65 Å) and three longer (2.85 Å) Mo–Mo bond lengths. There are a spread of Mo–Co bond distances ranging from 2.70–2.88 Å. In the second Mo site, Mo is bonded in a 10-coordinate geometry to seven Mo and nine equivalent Co atoms. There are a spread of Mo–Mo bond distances ranging from 2.69–2.85 Å. There are three shorter (2.75 Å) and six longer (2.91 Å) Mo–Co bond lengths. In the third Mo site, Mo is bonded in a 8-coordinate geometry to eight Mo and six equivalent Co atoms. There are a spread of Mo–Mo bond distances ranging from 2.52–3.04 Å. All Mo–Co bond lengths are 2.60 Å. In the fourth Mo site, Mo is bonded in a 8-coordinate geometry to eight Mo and six equivalent Co atoms. There are three shorter (3.02 Å) and three longer (3.05 Å) Mo–Mo bond lengths. All Mo–Co bond lengths are 2.60 Å. In the fifth Mo site, Mo is bonded in a 6-coordinate geometry to six Mo and six Co atoms. There are three shorter (2.63 Å) and three longer (2.69 Å) Mo–Co bond lengths. In the sixth Mo site, Mo is bonded in a 6-coordinate geometry to six Mo and six Co atoms. There are three shorter (2.65 Å) and three longer (2.69 Å) Mo–Co bond lengths. In the seventh Mo site, Mo is bonded to six equivalent Mo and six equivalent Co atoms to form distorted MoCo6Mo6 cuboctahedra that share corners with twelve equivalent CoCo4Mo8 cuboctahedra, edges with six equivalent MoCo6Mo6 cuboctahedra, and faces with eighteen equivalent CoCo4Mo8 cuboctahedra. All Mo–Co bond lengths are 2.47 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded to eight Mo and four equivalent Co atoms to form distorted CoCo4Mo8 cuboctahedra that share corners with two equivalent MoCo6Mo6 cuboctahedra, corners with thirteen CoCo4Mo8 cuboctahedra, edges with five CoCo4Mo8 cuboctahedra, faces with three equivalent MoCo6Mo6 cuboctahedra, and faces with ten equivalent CoCo4Mo8 cuboctahedra. There are two shorter (2.34 Å) and two longer (2.43 Å) Co–Co bond lengths. In the second Co site, Co is bonded to seven Mo and five Co atoms to form CoCo5Mo7 cuboctahedra that share corners with fifteen CoCo4Mo8 cuboctahedra, edges with five CoCo5Mo7 cuboctahedra, and faces with thirteen CoCo5Mo7 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.38–2.41 Å. In the third Co site, Co is bonded to six equivalent Mo and six equivalent Co atoms to form CoCo6Mo6 cuboctahedra that share corners with twelve equivalent CoCo5Mo7 cuboctahedra, edges with six equivalent CoCo6Mo6 cuboctahedra, and faces with eighteen equivalent CoCo5Mo7 cuboctahedra.