Visualizing screening in noble-metal clusters: static vs. dynamic

Rajarshi Sinha-Roy (1, 2, 3) , Pablo García-González (4) , Xóchitl López-Lozano (5) , Hans-Christian Weissker (2)

1 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
2 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille
3 ILM - Institut Lumière Matière [Villeurbanne]
4 UAM - Universidad Autónoma de Madrid
5 UTSA Department of Physics and Astronomy [San Antonio]

The localized surface-plasmon resonance of metal nanoparticles and clusters corresponds to a collective charge oscillation of the quasi-free metal electrons. The polarization of the more localized d electrons opposes the overall polarization of the electron cloud and thus screens the surface plasmon. By contrast, a static electric external field is well screened, as even very small noble-metal clusters are highly metallic: the field inside is practically zero except for the effect of the Friedel-oscillation-like modulations which lead to small values of the polarization of the d electrons. In the present article, we present and compare representations of the induced densities (i) connected to the surface-plasmon resonance and (ii) resulting from an external static electric field. The two cases allow for an intuitive understanding of the differences between the dynamic and the static screening.

Domaines: Chimie théorique et/ou physique; Matériaux

Rajarshi Sinha-Roy, Pablo García-González, Xóchitl López-Lozano, Hans-Christian Weissker. Visualizing screening in noble-metal clusters: static vs. dynamic. Physical Chemistry Chemical Physics, 2023, 25 (3), pp.2075-2083. ⟨10.1039/D2CP04316E⟩. ⟨hal-03935113⟩