Optical absorption spectroscopy of sodium clusters as measured by collinear molecular beam photodepletion

Abstract

Collinear molecular beam photodepletion was used to obtain particle specific electronic absorption information for Na3, Na4, and Na8 in a wavelength range from 370–835 nm. We critically discuss the experimental method used and the deconvolution procedure applied to the resulting data to yield absolute absorption cross sections. The spectra contain much information on the cluster-size–dependent transition from molecular to bulk-like optical response and are interpreted in terms of various computational approaches ranging from classical electrostatic to ab initio large scale configuration interaction.