Materials Data on Er6Al7Cu16 by Materials Project
Er6Cu16Al7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Er is bonded in a 12-coordinate geometry to eight Cu and four equivalent Al atoms. There are four shorter (2.92 Å) and four longer (3.03 Å) Er–Cu bond lengths. All Er–Al bond lengths are 3.09 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a 7-coordinate geometry to three equivalent Er, three equivalent Cu, and four Al atoms. All Cu–Cu bond lengths are 2.66 Å. There are one shorter (2.59 Å) and three longer (2.67 Å) Cu–Al bond lengths. In the second Cu site, Cu is bonded in a 12-coordinate geometry to three equivalent Er, six Cu, and three equivalent Al atoms. All Cu–Cu bond lengths are 2.68 Å. All Cu–Al bond lengths are 2.50 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a body-centered cubic geometry to eight equivalent Cu atoms. In the second Al site, Al is bonded to four equivalent Er and eight Cu atoms to form a mixture of distorted corner and face-sharing AlEr4Cu8 cuboctahedra.