Chemistry and Chemical Intermediates in Supersonic Free Jet Expansions

Science  10 Feb 1984:
Vol. 223, Issue 4636, pp. 545-553
DOI: 10.1126/science.223.4636.545


Short-lived intermediates often play key roles in determining the course of chemical reactions. Recently the combination of sophisticated laser techniques and supersonic free jet expansions has offered new insight into the structure and reactivity of such intermediates. Because of their extremely reactive nature the intermediates are produced in situ in the expansion. The free jet expansion provides cooling of the intermediates to very low temperatures, so that even complex organic free radicals and molecular ions can be identified and characterized. Radical-radical reactions and ionic cluster formation likewise proceed in the expansion and can be monitored by laser spectroscopy.