Oxidation-Induced Transformation of Eight-Electron Gold Nanoclusters: [Au 23 (SR) 16 ] - to [Au 28 (SR) 20 ] 0 .

Here we report an oxidation-induced transformation of [Au23 (S-c-C6 H11 )16 ]- TOA+ (S-c-C6 H11 : cyclohexanethiolate; TOA: tetraoctylammonium) to the [Au28 (S-c-C6 H11 )20 ]0 nanocluster by H2 O2 treatment under ambient conditions. This is the first example of oxidation-induced transformation of one stable size to another with atomic precision. The product was crystallized and analyzed by X-ray crystallography. Further insights into the transformation process were obtained by monitoring the process with optical spectroscopy and also by electrochemical analysis. This work adds a new dimension to the recently established transformation chemistry of nanoclusters that involves size and structure transformations.