Systematic Study ofAu6toAu12Gold Clusters on MgO(100)FCenters Using Density-Functional Theory

Abstract

We present an optimized genetic algorithm used in conjunction with density-functional theory in the search for stable gold clusters and ${\mathrm{O}}_2$ adsorption ensembles in $F$ centers at MgO(100). For ${\mathrm{Au}}_8$ the method recovers known structures and identifies several more stable ones. When ${\mathrm{O}}_2$ adsorption is investigated, the genetic algorithm is used to imitate structural fluxionality, increasing the ${\mathrm{O}}_2$ bond strength by up to 1 eV. Extending the method to ${\mathrm{Au}}_{6,10,12}$, strong ${\mathrm{O}}_2$ adsorption configurations are found for all sizes. However, the effect of fluxionality appears to wear off with increasing cluster size. DOI: http://dx.doi.org/10.1103/PhysRevLett.108.126101 © 2012 American Physical Society