Infrared photochemistry

Sulphur hexafluoride still commands considerable attention. Single-photon excitation of V3 = 1 has been studied in high-resolution diode-infrared laser 

Double-resonance experiments involving i.r. pumping followed by visible or u.v. laser probing of the vibrationally excited species have been reported by several groups. Laser-induced fluorescence of thiophosgene following MPA of COj radiation at intensities 3 MW cm has shown that the vibrational populations of i = 0—4,6, and 8 of the V4 mode are depleted or not populated under collision-free conditions when the initially pumped mode is 2v, and only at lower laser intensities are population increases in these levels observed. It appears that all 

Ashfold and G. Hancock, Infrared Multiple Photon Excitation and Dissociation Reaction Kinetics and Radical Formation , in Gas Kinetics and Energy Transfer, ed. P. G. Ashmore and R. J. Donovan (Specialist Periodical Reports), The Royal Society of Chemistry, London, 1981, Vol. 4, p. 73. 

Renlund, H. Reisler, and C. Wittig, Chem. Phys. Lett., 1981, 78, 40. 

The effects of magnetic and electric fields have been found to increase the 

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With the development of CO 2 lasers, work on the infrared photochemistry of boron compounds is now appearing in the literature. Future woric on these compounds with UV laser sources is also expected. In this review the effect of radiation on boron compounds in the photon energy range 0.1 eV (CO2 laser) to 10.2 eV (H-a line) is examined. The range of tropics extends from the use of photochemical techniques for synthesis of new compounds to the production and isolation of reactive photochemical intermediates. The photochemistry of borazine is most extensively discussed. 

Graener H, Ye TQ, Laubereau A. Ultrafast vibrational predissociation of hydrogen bonds mode selective infrared photochemistry in liquids. I Chem Phys 1989 91 1043-1046. 

Miller, S. S. DeFord, D. D. Marks, T. J. Weitz, E. "Infrared Photochemistry of a Volatile Uranium Compound... 

Finally in this Section on infrared photochemistry, the i.r. laser-induced reaction of SF with a Si surface has been described. Pulsed COj laser radiation in the absence of SF causes momentary heating of a Si target, but no Si removal in the presence of a few Torr of SF, etching of the Si is observed. The mechanism for the process is yet to be established, but it appears that both the reactions of excited species produced by the laser, and the effect of the laser radiation at the gas-surface interface are of importance. ... 

The infrared photochemistry of SF continues to attract considerable interest. One important study involves excitation of SFg in high-resolution diode-infrared laser double resonance experiments. At high intensities, and 30 ps infrared pulses, spectral hole burning is observed at energies corresponding to the absorption of between 4 and 5 photons per molecule (Reiser et al. cf. Sharp et al.). 

Beauchamp, J.L. Thome, L.R. Infrared Photochemistry of Gas Phase Ions. In Gas Phase Ion Chemistry Volume 3 Bowers, M.T., Ed. Academic Press, Inc. London, 1984, pp. 42-97. 

SINGLE-PHOTON INFRARED PHOTOCHEMISTRY WAVELENGTH AND TEMPERATURE DEPENDENCE OF THE QUANTUM YIELD FOR THE LASER INDUCED IONIZATION OF WATER... 

Goodall, D. M., Holzwarth, J. F., et al. 1979, this volume, "Single-Photon Infrared Photochemistry"... 

M. P. Casassa, D. S. Bomse, J. L. Beauchamp, and K. C. Janda, Infrared photochemistry of ethylene clusters, J. Chem. Phys. 

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