Journal of Physical Chemistry A, Vol.117, No.40, 10470-10476, 2013
Structure of the Thiolated Au-130 Cluster
The structure of the recently discovered Au-130-thiolate and -dithiolate clusters is explored in a combined experiment-theory approach. Rapid electron diffraction in scanning/transmission electron microscopy (STEM) enables atomic-resolution imaging of the gold core and the comparison with density functional theory (DFT)-optimized realistic structure models. The results are consistent with a 105-atom truncated-decahedral core protected by 25 short staple motifs, incorporating disulfide bridges linking the dithiolate ligands. The optimized structure also accounts, via time-dependent DFT (TD-DFT) simulation, for the distinctive optical absorption spectrum, and rationalizes the special stability underlying the selective formation of the Au-130 cluster in high yield. The structure is distinct from, yet shares some features with, each of the known Au-102 and Au-144/Au-146 systems.