TDDFT Study of the Optical Absorption Spectra of Bare Gold Clusters

Abstract

Time-dependent density functional theory (TDDFT) was used to calculate the optical absorption spectra of gold clusters of 20–171 atoms. The spectra for the smallest clusters agree with previous results, and the spectra for the largest clusters show features consistent with classical Mie theory. The systematic exploration of particles of sizes within these two extremes has allowed the trends linking optical absorption spectra and particle size and symmetry to be identified. A transition from molecular-like spectra to a more classical response is observed.