Materials Data on Al3Co(W3C)3 by Materials Project

Abstract

W9Al3CoC3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent W sites. In the first W site, W is bonded in a 2-coordinate geometry to one Co, three equivalent Al, and two equivalent C atoms. The W–Co bond length is 2.85 Å. There are two shorter (2.80 Å) and one longer (2.83 Å) W–Al bond lengths. Both W–C bond lengths are 2.16 Å. In the second W site, W is bonded in a distorted rectangular see-saw-like geometry to two equivalent Al and two equivalent C atoms. Both W–Al bond lengths are 2.66 Å. Both W–C bond lengths are 2.09 Å. Co is bonded to six equivalent W and six equivalent Al atoms to form CoAl6W6 cuboctahedra that share edges with six equivalent CW6 octahedra, faces with two equivalent CoAl6W6 cuboctahedra, and faces with six equivalent AlAl2Co2W8 cuboctahedra. All Co–Al bond lengths are 2.48 Å. Al is bonded to eight W, two equivalent Co, and two equivalent Al atoms to form distorted AlAl2Co2W8 cuboctahedra that share corners with four equivalent AlAl2Co2W8 cuboctahedra, corners with four equivalent CW6 octahedra, faces with two equivalent CoAl6W6 cuboctahedra, faces with six equivalent AlAl2Co2W8 cuboctahedra, and faces with four equivalent CW6 octahedra. The corner-sharing octahedral tilt angles are 39°. Both Al–Al bond lengths are 2.63 Å. C is bonded to six W atoms to form CW6 octahedra that share corners with four equivalent AlAl2Co2W8 cuboctahedra, corners with six equivalent CW6 octahedra, edges with two equivalent CoAl6W6 cuboctahedra, and faces with four equivalent AlAl2Co2W8 cuboctahedra. The corner-sharing octahedra tilt angles range from 40–46°.