Photochemistry on rough metal surfaces

Journal Article · Thu Sep 13 04:00:00 EDT 1984 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j150663a003· OSTI ID:6309322

Goncher, G M; Parsons, C A; Harris, C B

The general question of laser-induced photochemistry on metal surfaces is addressed. Specifically, the authors have studied resonant photodecomposition of a variety of aromatic molecules on roughened silver surfaces in ultrahigh vacuum. A continuous ion laser source at a number of different wavelengths in the region 350-410 nm was used to produce graphitic carbon on the surface which was monitored by Raman spectroscopy at the 1580-cm/sup -1/ band of surface carbon. Laser power-dependence studies of fragmentation rate for several molecules at 406.7nm indicate that the initial absorption step is a two-photon process. Energetic considerations imply that photochemistry for other molecules studied is also due to multiphoton absorption, except for benzaldehyde fragmentation at 350.7-nm excitation, where the photodecomposition rate is linear. Distance-dependence studies of photofragmentation rates by use of an inert spacer layer to separatte the molecule undergoing photochemistry from the surface indicate that energy transfer to the metal surface is important in determining the reaction rate. Decomposition mechanism has not been fully evaluated.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 6309322
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 88:19; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ADSORPTION
ALDEHYDES
AMINES
ANILINE
AROMATICS
AZINES
BENZALDEHYDE
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
DATA
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
KINETICS
LASER RADIATION
METALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOCHEMISTRY
PYRIDINE
PYRIDINES
RADIATIONS
RAMAN SPECTRA
REACTION KINETICS
SILVER
SORPTION
SPECTRA
SUBSTRATES
SURFACE PROPERTIES
TRANSITION ELEMENTS
ULTRAHIGH VACUUM
WAVELENGTHS