Materials Data on TbAlCu by Materials Project
TbCuAl crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Tb is bonded in a 5-coordinate geometry to five Cu and six equivalent Al atoms. There are one shorter (2.91 Å) and four longer (2.93 Å) Tb–Cu bond lengths. There are two shorter (3.20 Å) and four longer (3.24 Å) Tb–Al bond lengths. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a distorted q6 geometry to three equivalent Tb and six equivalent Al atoms. All Cu–Al bond lengths are 2.61 Å. In the second Cu site, Cu is bonded in a 9-coordinate geometry to six equivalent Tb and three equivalent Al atoms. All Cu–Al bond lengths are 2.76 Å. Al is bonded in a 12-coordinate geometry to six equivalent Tb, four Cu, and two equivalent Al atoms. Both Al–Al bond lengths are 2.84 Å.