Single-atom doping on thiolate-protected gold nanoclusters: A TDDFT study on the excited states

Abstract

The optical features of thiolate-protected gold nanoclusters can be tuned in different ways to achieve the desired features. One promising approach is doping with a single metallic atom to the gold core to form the 'Atomically Precise Gold Nanoparticle'. However, the tuning mechanism and the changes in the excited states are not discussed thoroughly. In this work, we perform theoretical analyses of Ag, Cu, Pd, and Pt doped gold nanoclusters and focus on the doping induced changes in the excitations. Our results indicate several significant impacts of the platinum family dopings, which are not presented in the gold family dopings: low energy (infrared) excitation features, extra 'in-gap' energy levels, and significant redistribution of the electrons/holes in response to the external electric field.