Experimental study of the CO:O3 complex in argon matrices: Irradiation at 266 nm.

Autor: Raducu, V., Jasmin, D., Dahoo, R., Brosset, P., Gauthier-Roy, B., Abouaf-Marguin, L.
Předmět:
Zdroj: Journal of Chemical Physics; 8/1/1994, Vol. 101 Issue 3, p1878, 7p
Abstrakt: Codeposition of argon dilute samples of O3 and CO produced new narrow absorption lines which are assigned to the CO:O3 complex. One line appears at 2140.44 cm-1, 2 cm-1 above the CO frequency which shows that it is a weakly bonded complex. Its spectrum exhibits three new lines near the ν3 doublet of O3. The two lines observed at 1042.56 and 1043.37 cm-1 appear clearly at 5 K; the lowest frequency one, at 1041.35 cm-1, is overlapped at 5 K by the high frequency component of the ν3 doublet of isolated O3 and can only be detected when the temperature is raised, as it is almost not temperature dependent up to 20 K. Irradiation of the sample at 5 K with the 266 nm emission of a quadrupled ND-YAG laser leads to an efficient decomposition of free and complexed ozone and an increase of CO2 with two regimes, a fast beginning similar to the O3 and CO:O3 decays followed by a much slower one. After such an irradiation at 5 K, some recombination of O3 and CO:O3 is observed during a warming at 10 K. A careful analysis of the relative intensities variation shows that CO2 is only produced inside the CO:O3 complex, from the reaction of CO with 1D atomic oxygen. As 1D oxygen atoms are very fastly relaxed to 3P ones during their migration through the matrix, isolated CO does not react. We have shown evidence of a very limited migration of atomic oxygen at 5 K in solid argon, and of an efficient one at 10 K. [ABSTRACT FROM AUTHOR]
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