Materials Data on Co4Ge by Materials Project

Abstract

Co4Ge is Molybdenum Carbide MAX Phase-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Co sites. In the first Co site, Co is bonded to five Co and one Ge atom to form CoCo5Ge octahedra that share corners with six CoCo5Ge octahedra, edges with four equivalent GeCo2Ge4 octahedra, and edges with eight CoCo5Ge octahedra. The corner-sharing octahedral tilt angles are 0°. There are one shorter (2.27 Å) and four longer (2.43 Å) Co–Co bond lengths. The Co–Ge bond length is 2.47 Å. In the second Co site, Co is bonded to six Co atoms to form CoCo6 octahedra that share a cornercorner with one GeCo2Ge4 octahedra, corners with five CoCo5Ge octahedra, and edges with twelve CoCo5Ge octahedra. The corner-sharing octahedral tilt angles are 0°. There are one shorter (2.31 Å) and four longer (2.43 Å) Co–Co bond lengths. Ge is bonded to two equivalent Co and four equivalent Ge atoms to form GeCo2Ge4 octahedra that share corners with two equivalent CoCo6 octahedra, corners with four equivalent GeCo2Ge4 octahedra, edges with four equivalent GeCo2Ge4 octahedra, and edges with eight equivalent CoCo5Ge octahedra. The corner-sharing octahedral tilt angles are 0°. All Ge–Ge bond lengths are 2.43 Å.