Materials Data on TmBeCu4 by Materials Project
BeTmCu4 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Be is bonded to three equivalent Tm and nine Cu atoms to form a mixture of distorted corner and edge-sharing BeTm3Cu9 cuboctahedra. All Be–Tm bond lengths are 2.92 Å. There are a spread of Be–Cu bond distances ranging from 2.36–2.89 Å. Tm is bonded in a 10-coordinate geometry to three equivalent Be and thirteen Cu atoms. There are a spread of Tm–Cu bond distances ranging from 2.84–3.02 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a 4-coordinate geometry to three equivalent Be, four equivalent Tm, and nine equivalent Cu atoms. There are three shorter (2.76 Å) and six longer (2.90 Å) Cu–Cu bond lengths. In the second Cu site, Cu is bonded in a 12-coordinate geometry to two equivalent Be, three equivalent Tm, and seven Cu atoms. There are two shorter (2.46 Å) and two longer (2.51 Å) Cu–Cu bond lengths.