Racemization of chiral Pd2Au36(SC2H4Ph)24: doping increases the flexibility of the cluster surface.

ABSTRACT

Pd2Au36(SC2H4Ph)24 clusters have been prepared, isolated and separated in their enantiomers. Compared to the parent Au38(SC2H4Ph)24 cluster, the doping leads to a significant change of the circular dichroism spectrum; however, the anisotropy factors are of similar magnitude in both cases. Isolation of the enantiomers allowed us to study the racemization of the chiral cluster, which reflects the flexibility of the ligand shell composed of staple motifs. The doping leads to a substantial lowering of the racemization temperature. The change in activation parameters due to the doping may be solely due to modification of the electronic structure.