Ring Model for Understanding How Interfacial Interaction
Dictates the Structures of Protection Motifs and Gold Cores in Thiolate-Protected
Gold Nanoclusters
Understanding
the effect of interfacial interactions between the
protection motifs and gold cores on the stabilities of thiolate-protected
gold nanoclusters is still a challenging task. Based on analyses of
95 experimentally crystallized and theoretically predicted thiolate-protected
gold nanoclusters, we present a ring model to offer a deeper insight
into the interfacial interactions for this class of nanoclusters.
In the ring model, all the gold nanoclusters can be generically viewed
as a fusion or interlocking of several [Aum(SR)n] (m = 4–8,
10, and 12 and 0 ≤ n ≤ m) rings. Guided by the ring model and the grand unified model, a
new Au42(SR)26 isomer is predicted, whose total
energy is lower than those of two previously crystallized isomers.
The ring model offers a mechanistic understanding of the interactions
between the protection ligands and gold cores and practical guidance
on predicting new gold nanoclusters for future experimental synthesis
and confirmation.