Zeitschrift für Physik

, Volume 234, Issue 4, pp 307–318

Kramers Kronig analysis of the optical properties of small silver particles

  • U. Kreibig

DOI: 10.1007/BF01394718

Cite this article as:
Kreibig, U. Z. Physik (1970) 234: 307. doi:10.1007/BF01394718


In order to complete a preceding paper the dielectric constantɛ of the particle material of small silver particles with diameters between 210 and 25 Å is computed in the wavelength region 365≦λ≦455 nm from the measured spectra of thesmall particle plasma reasonance absorption.

For this purpose a properKramers Kronig relation is derived, and is checked by applying to particles with Drude free electron gas.

The results, concerning the silver particles, are that the real part ofɛ changes slightly, whereas the imaginary part is markedly enhanced (up to the ten-fold of the bulk values) if the particle size decreases.

This size dependence ofɛ can quantitatively be described with thefree path effect within the accuracy of the measured values.

Conversely, thebulk dielectric constant of silver is obtained by applying the free path effect to the measured dielectric constant of the small particles.

Copyright information

© Springer-Verlag 1970

Authors and Affiliations

  • U. Kreibig
    • 1
  1. 1.Institut für Experimentalphysik I der Universität des SaarlandesSaarbrücken