Interaction between SiO₂ Surface and Au Clusters Studied by Computational Chemistry

We proposed a new method to evaluate the interaction between a substrate and metal clusters based on computational chemistry with a reduced calculation time. This method is applied to study the interaction between a SiO₂ surface and Au clusters to elucidate the potential energy as well as the energetics of Au clusters on the SiO₂ surface. The method comprises three steps. The first step is evaluation of the interaction between the SiO₂ surface and Au atom using ab initio calculation. Secondly, we determine the parameters that are used in two-body potential functions to reproduce the interaction evaluated by ab initio calculation. In the third step, we investigate the interaction between a SiO₂ surface and Au clusters using the two-body potential functions. This study reveals that the atomic-scale roughness of the substrate surface predominantly determined the most stable point of the Au clusters on the SiO₂ substrate. We also find that the shape and orientation of the Au clusters affect the interaction.