Optical Properties of Noble Metal Clusters from the Ab Initio Perspective

H.-Ch. Weissker (1)

1 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille

The peculiar optical properties of noble-metal clusters and nanoparticles are mostly governed by the localized surface-plasmon resonance (LSPR). The strong absorption arising from the LSPR in the visible and the near-UV parts of the spectrum of many clusters enables a multitude of applications. Here, we review the physical effects that dominate and influence the optical properties of noble-metal clusters in different size ranges, focusing in particular on the emergence phenomenon of the LSPR in gold clusters and on the presence of individual structure in the spectra which provide information on the cluster's quantum nature. Basic difficulties arising for experimental measurements of the optical properties are mentioned. We likewise discuss the different theoretical approaches suitable for the different size ranges. Atomistic Time-Dependent Density-Functional Theory (TDDFT) is widely used for the description of noble-metal clusters of intermediate size, viz., between the molecule-like structures comprising but a few atoms and sizes of about 2 nm. We discuss the basics of these ab initio TDDFT calculations, with a particular focus on the time-evolution approach. We discuss the present possibilities, strengths, and limitations of the method and compare briefly with the linear-response formalism. Finally, we discuss examples that highlight the strengths of the present TDDFT methods.

Mots clés: density-functional theory; time-dependent density-functional theory; clusters; noble-metal; TDDFT; ab initio; surface-plasmon resonance; single-particle mea-surements; linear response; RT-TDDFT; time-evolution; monolayer-protected clusters; optical properties

Domaines: Matière Condensée [cond-mat]; Physique Numérique [physics.comp-ph]; Chimie théorique et/ou physique

H.-Ch. Weissker. Optical Properties of Noble Metal Clusters from the Ab Initio Perspective. Klaus Wandelt. Encyclopedia of Interfacial Chemistry, Elsevier, pp.546-558, 2018, 9780128097397. ⟨hal-02002264⟩