Materials Data on Tm6Al7Cu16 by Materials Project
Tm6Cu16Al7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Tm is bonded in a 12-coordinate geometry to eight Cu and four equivalent Al atoms. There are four shorter (2.94 Å) and four longer (3.01 Å) Tm–Cu bond lengths. All Tm–Al bond lengths are 3.09 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a 12-coordinate geometry to three equivalent Tm, six Cu, and three equivalent Al atoms. All Cu–Cu bond lengths are 2.67 Å. All Cu–Al bond lengths are 2.49 Å. In the second Cu site, Cu is bonded in a 7-coordinate geometry to three equivalent Tm, three equivalent Cu, and four Al atoms. There are one shorter (2.55 Å) and three longer (2.67 Å) Cu–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded to four equivalent Tm and eight Cu atoms to form a mixture of distorted face and corner-sharing AlTm4Cu8 cuboctahedra. In the second Al site, Al is bonded in a body-centered cubic geometry to eight equivalent Cu atoms.