Surface enhanced Raman scattering (SERS) by molecules adsorbed at spherical particles: errata.

Area of Science:

• Physical Chemistry
• Surface Science
• Spectroscopy

Background:

• Surface-Enhanced Raman Scattering (SERS) is observed at roughened metal surfaces.
• The electromagnetic mechanism is a proposed explanation for SERS.

Purpose of the Study:

• To develop a model for Raman scattering from a molecule adsorbed on a spherical particle.
• To investigate the potential for SERS on spherical particles and its similarity to roughened electrodes.

Main Methods:

• A classical electric dipole model for the adsorbed molecule.
• Calculation of incident, near-scattered, and emitted fields.
• Analysis of feedback terms between the dipole and particle.

Main Results:

• A model for Raman scattering by adsorbed molecules on spherical particles was developed.
• Significant SERS enhancement (~10^6) was predicted for pyridine on a silver sphere under specific conditions (excitation wavelength ~382 nm).
• Angular distribution and polarization of Raman emission were analyzed concerning particle size, molecule distance, and excitation wavelength.

Conclusions:

• The electromagnetic mechanism elucidated here may explain SERS at roughened silver electrodes.
• Comparable effects are predicted for fluorescent scattering.