Interfacial Infrared Vibrational Spectroscopy.
Abstract
Vibrational spectra of species on or near metal surfaces are subject to a unique surface selection rule due to the physics of reflection of radiation from a highly conducting surface. As shown in Fig. 1, s-polarized radiation (electric vector perpendicular to the plane of incidence) at all angles of incidence undergoes a phase shift close to 180 C. P-polarized radiation (electronic vector in plane of incidence) has a phase change upon reflection which varies with the angle of incidence as also shown in Fig. 1. Light reflected from a metal surface combines with the incident light to form a standing wave electric field whose intensity is shown in Fig. 2. The mechanism for absorption of infrared radiation requires a coupling of the electric field with a molecular vibration. Since the intensity of the standing wave electric field parallel to the surface is near zero, only those modes of a species near the metal surface which produce a fluctuation in the dipole moment with component normal to the surface can absorb energy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 30, 1986
- Accession Number
- ADA193748
Entities
People
- Joel Russell
- John K. Foley
- Mark Seversen
- Stanley Pons
Organizations
- University of Utah