Studies of the Augmentation of Reaction Rates via Laser Irradiation in the Infrared.
Abstract
The objective of this research project, to discover a reaction, involving a sizable substrate (more than three atoms) the rate of which is selectively augmented by infrared laser radiation, has been achieved. A preliminary analysis led to criteria for the selection of an optimum reaction type, and for setting the most suitable experimental parameters. We selected to study the self-scavenging decomposition of a borane adduct: 2 H3BPF3 yields B2H6 + 2PF3. The relative photolytic efficiencies of the various lines emitted by a CO2 laser were measured as was also the dependence of the rate on laser power, gas pressure and reaction cell temperature. Specificity of vibrational excitation was demonstrated in several ways, most directly by the observed isotope fractionation of H/D and 10 sub B/11 sub B ratios. The mechanism of the photoactivation process which we developed is in quantitative agreement with the observed conversion. A dynamic model (based on a normal mode analysis) was proposed for the selective activation. In a parallel study of borane adducts, we evaluated the thermodynamic and kinetic rate parameters for six exchange and abstraction reactions. Rational structures were proposed for the corresponding transition states. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 15, 1976
- Accession Number
- ADA033503
Entities
People
- Earl R. Lory
- Kuei-ru Chien
- S. H. Bauer
Organizations
- Cornell University Department of Chemistry and Chemical Biology