Colloid and Polymer Science

, Volume 274, Issue 7, pp 648–653

Effect of a surface charge on the halfwidth and peak position of cluster plasmons in colloidal metal particles

  • J. Rostalski
  • M. Quinten
Original Contribution

DOI: 10.1007/BF00653063

Cite this article as:
Rostalski, J. & Quinten, M. Colloid Polym Sci (1996) 274: 648. doi:10.1007/BF00653063


The optical response of colloidal particles depends on a variety of properties of the cluster, e.g., shape, size, size distribution and particle material. Since particles often are charged, also the surface charge may be a parameter which influences their optical properties. In this paper the effect of a surface charge on optical properties of spherical colloidal particles is studied and its magnitude is estimated by extended computations for silver clusters with surface plasmon in aqueous suspension. Two models are presented and discussed. The first model is based on the electrodynamic solution by Bohren and Hunt (Can. J. Phys. 55, 1930 (1977)), where a surface conductivity σS for a free surface charge yield an additional contribution εS to the dielectric constant of the particle material. In the second model, the surface charge contributes to the number density of free electrons in the cluster. Both models lead to a shift of the cluster plasmon peak, while an increase of the plasmon halfwidth could not be derived. The effect is quite small and limited on very small clusters.

Key words

Surface chargecolloidal particlescharged clusterscluster plasmonblue shiftred shift

Copyright information

© Steinkopff Verlag 1996

Authors and Affiliations

  • J. Rostalski
    • 1
  • M. Quinten
    • 1
  1. 1.1. Physikalisches InstitutRWTH AachenAachenGermany