Materials Data on Ta6Co16Si7 by Materials Project

Abstract

Ta6Co16Si7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ta is bonded in a 12-coordinate geometry to eight Co and four equivalent Si atoms. There are four shorter (2.65 Å) and four longer (2.74 Å) Ta–Co bond lengths. All Ta–Si bond lengths are 2.84 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 7-coordinate geometry to three equivalent Ta, six Co, and four Si atoms. There are three shorter (2.52 Å) and three longer (2.64 Å) Co–Co bond lengths. There are one shorter (2.29 Å) and three longer (2.46 Å) Co–Si bond lengths. In the second Co site, Co is bonded in a 12-coordinate geometry to three equivalent Ta, six Co, and three equivalent Si atoms. All Co–Co bond lengths are 2.65 Å. All Co–Si bond lengths are 2.28 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a body-centered cubic geometry to eight equivalent Co atoms. In the second Si site, Si is bonded to four equivalent Ta and eight Co atoms to form a mixture of face and corner-sharing SiTa4Co8 cuboctahedra.