Materials Data on NbAlCo4 by Materials Project

Abstract

NbCo4Al is Hexagonal Laves-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Nb is bonded in a 12-coordinate geometry to three equivalent Nb, twelve Co, and one Al atom. All Nb–Nb bond lengths are 3.03 Å. There are a spread of Nb–Co bond distances ranging from 2.69–2.91 Å. The Nb–Al bond length is 2.78 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded to six equivalent Co and six equivalent Al atoms to form CoAl6Co6 cuboctahedra that share corners with twelve equivalent CoNb3Al3Co6 cuboctahedra, edges with six equivalent CoAl6Co6 cuboctahedra, and faces with twenty CoNb6Co6 cuboctahedra. All Co–Co bond lengths are 2.35 Å. All Co–Al bond lengths are 2.76 Å. In the second Co site, Co is bonded to six equivalent Nb and six equivalent Co atoms to form CoNb6Co6 cuboctahedra that share corners with twelve equivalent CoNb3Al3Co6 cuboctahedra, edges with six equivalent CoNb6Co6 cuboctahedra, and faces with twenty CoAl6Co6 cuboctahedra. All Co–Co bond lengths are 2.38 Å. In the third Co site, Co is bonded to three equivalent Nb, six Co, and three equivalent Al atoms to form CoNb3Al3Co6 cuboctahedra that share corners with eighteen CoAl6Co6 cuboctahedra, edges with six equivalent CoNb3Al3Co6 cuboctahedra, and faces with eighteen CoAl6Co6 cuboctahedra. There are two shorter (2.33 Å) and two longer (2.40 Å) Co–Co bond lengths. There are one shorter (2.65 Å) and two longer (2.80 Å) Co–Al bond lengths. Al is bonded in a 12-coordinate geometry to one Nb, twelve Co, and three equivalent Al atoms. All Al–Al bond lengths are 2.84 Å.