Gas-phase Photoprocesses

Gas-phase photoprocesses is an area that has developed enormously since the appearance of the first volume of Photochemistry in 1970. This growth is reflected in almost every subsequent volume, as the reporters have had to accommodate an expanding literature covering many apparently diverse aspects of gas-phase chemistry, I am taking this opportunity to experiment with the style and presentation of this Chapter, making use of tabulated information as a source for the interested research worker and reserving the text for a slightly fuller description of new material. Emphasis has also been directed more toward processes than individual species. 

Coherent anti-Stokes Raman scattering, CARS, appears to be a promising spectroscopic method of investigating vibrationally excited intermediates formed in isomerization reactions of large polyatomic molecules. The state of cycloheptatriene and its 7-methyl derivative, formed by absorption at 266 nm. 

Rate constants for reaction of the CH radical with a number of atomic and molecular collision partners have been reported, with multiple-photon dissociation of suitable precursor molecules using either infrared or ultraviolet laser radiation used as the pulsed photolysis source, and laser-induced fluorescence near 431 nm employed as a sensitive time-resolved detection method. A similar technique has been used to measure removal rates of CH2 and CDj with 

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