Localized surface plasmon resonance in silver nanoparticles: Atomistic first-principles time-dependent density-functional theory calculations

TL;DR

This study uses first-principles time-dependent density-functional theory to analyze localized surface plasmon resonances in silver nanoparticles, showing convergence to classical behavior at sizes between 1 and 2 nm.

Contribution

It introduces a novel ab initio simulation approach combining GLLB-SC functional with real-time propagation for silver nanoparticles, bridging quantum and classical plasmon models.

Findings

Resonances enter the asymptotic region between 1-2 nm

Resonances converge near 3.4 eV, close to classical limit

Good agreement with experimental and modeled data

Abstract

We observe using ab initio methods that localized surface plasmon resonances in icosahedral silver nanoparticles enter the asymptotic region already between diameters of 1 and 2 nm, converging close to the classical quasistatic limit around 3.4 eV. We base the observation on time-dependent density-functional theory simulations of the icosahedral silver clusters Ag$_{55}$ (1.06 nm), Ag$_{147}$ (1.60 nm), Ag$_{309}$ (2.14 nm), and Ag$_{561}$ (2.68 nm). The simulation method combines the adiabatic GLLB-SC exchange-correlation functional with real time propagation in an atomic orbital basis set using the projector-augmented wave method. The method has been implemented for the electron structure code GPAW within the scope of this work. We obtain good agreement with experimental data and modeled results, including photoemission and plasmon resonance. Moreover, we can extrapolate the ab initio results to the classical quasistatically modeled icosahedral clusters.