Effects of Rare-Gas Matrices on the Optical Response of Silver Nanoclusters

Abstract

The optical response of silver clusters, Agn with n = 8, 20, 35, 58, and 92, embedded in a rare-gas matrix are calculated in the framework of the time-dependent density functional theory (TDDFT). We present a methodology able to reproduce with unprecedented accuracy the experimental spectra measured on metal clusters embedded in neon, argon, krypton, and xenon solid matrices. In our approach, the metal cluster is surrounded by explicit rare-gas atoms and embedded in a polarizable continuum medium. Interactions with the surrounding medium affect both the position and the width of the surface plasmon absorption band of metal clusters. The size-dependent shift of the surface plasmon band is evaluated in the case of a neon matrix. While the band shifts to lower energies (red shift) for large clusters, it shifts to higher energies (blue shift) for very small clusters.