Racemization of chiral Pd2Au36(SC2H4Ph)24: doping increases the flexibility of the cluster surface.
نویسندگان
چکیده
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.
منابع مشابه
Palladium doping of magic gold cluster Au38(SC2H4Ph)24: formation of Pd2Au36(SC2H4Ph)24 with higher stability than Au38(SC2H4Ph)24.
A phenylethanethiolate-protected Pd(2)Au(36)(SC(2)H(4)Ph)(24) cluster, which is a two-Pd atom-doped cluster of the well studied magic gold cluster Au(38)(SC(2)H(4)Ph)(24), was synthesized in high purity and its stability was investigated. The results demonstrate that Pd(2)Au(36)(SC(2)H(4)Ph)(24) is more stable than Au(38)(SC(2)H(4)Ph)(24) against degradation in solution and core etching by thiols.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 136 41 شماره
صفحات -
تاریخ انتشار 2014