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Science 7 July 1967:
Vol. 157. no. 3784, pp. 40 - 43
DOI: 10.1126/science.157.3784.40
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Articles

Selective Laser Photocatalysis of Bromine Reactions

Laser light excites gaseous bromine molecules to single bound quantum states near the dissociation continuum

W. B. Tiffany 1, H. W. Moos 2, and A. L. Schawlow 3

1 Stanford University, Stanford, California
2 Johns Hopkins University, Baltimore, Maryland
3 Stanford University

The results have shown that selective excitation obtained with a tunable monochromatic laser is a useful technique for studying photochemical and energy transfer processes. A new phenomenon in the photochemistry of bromine was observed, in which bound excited molecules, and not atoms, were formed in the primary process. The mechanism of the subsequent reaction consists of collisional dissociation of the excited molecules into atoms, which then initiated free-radical chains. A quantitative estimate of the collisional electronic relaxation rate for excited bromine molecules was obtained, and a new upper limit to the continuous absorption strength at 14,400 cm-1 was determined.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Spectroscopy in a New Light.
A. L. Schawlow and A. L. Schawlow (1982)
Science 217, 9-16
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Use of Lasers to Control Selective Chemical Reactions.
V. S. Letokhov (1973)
Science 180, 451-458
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Science. ISSN 0036-8075 (print), 1095-9203 (online)