Fundamental optical studies of competitive adsorption and thin film phenomena: Progress report for period July 1, 1986-June 30, 1987

Technical Report · Wed Apr 01 00:00:00 EST 1987

OSTI ID:6806402

Furtak, T E

The program has provided insight into the mechanisms of surface-enhanced Raman scattering and optical second harmonic generation. New information was also obtained on the electrolyte-metal interface, particularly with regard to the role of chloride ions. The active site was identified in surface enhanced Raman scattering from silver substrates. It was shown that Ag/sub 4//sup +/, stabilized by low temperature or by coadsorption provide specific enhancement, caused by resonance within the silver cluster. Other experiments showed that local field effects dominate the shift of vibrational energy with applied potential in the Ag-Cl system. Several forms of adsorbed chloride were identified. Some are associated with the surface Raman active site stabilization and others represent ''ordinary'' adsorbed chloride. Optical second harmonic generation studies on underpotential deposited metal films on single crystal samples have shown that some overlayers (Cu, Zn, Cd) demonstrate intrinsic resonance related to the electronic structure of the layer. Other overlayers (Tl, Bi) modify the electron dynamics or density within the substrate. Information has been obtained about the growth sequence for Cu on Ag.

• Research Organization: Colorado School of Mines, Golden (USA). Dept. of Physics
• DOE Contract Number: FG02-86ER45253
• OSTI ID: 6806402
• Report Number(s): DOE/ER/45253-1; ON: DE87010083
• Resource Relation: Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CADMIUM
ADSORPTION
CHLORIDES
COPPER
SILVER
SORPTIVE PROPERTIES
ZINC
ELECTRONIC STRUCTURE
HARMONICS
LAYERS
RAMAN EFFECT
RESEARCH PROGRAMS
RESONANCE
SCATTERING
SOLID CLUSTERS
SURFACES
THIN FILMS
CHLORINE COMPOUNDS
ELEMENTS
FILMS
HALIDES
HALOGEN COMPOUNDS
METALS
OSCILLATIONS
SORPTION
SURFACE PROPERTIES
TRANSITION ELEMENTS
360104* - Metals & Alloys- Physical Properties