LASER PHOTOLYSIS OF OCLO IN SOLID NE, AR, AND KR - II - SITE SELECTIVITY, MODE SPECIFICITY, AND EFFECTS OF MATRIX HOSTS

Irradiation of low-lying vibronic levels of (A) over tilde (2)A(2) Of OClO isolated in solid Ne, Ar, or Kr produces ClOO. Destruction of OCl O and production of ClOO in various matrix sites were monitored with I R absorption lines near 1100 and 1440 cm(-1), respectively. For OClO i n solid Ar at 5 K, site selectivity is observed after irradiation at t he vibronic line associated with a specific site; decreased intensity of the IR line associated with a specific site of OClO correlates well with increased intensity of the corresponding line of ClOO. Similar b ehavior is observed for OClO in solid Kr except that formation of ClOO in one site (1412.1 cm(-1)) is invariably dominant. The nature of the carriers of two major sites of ClOO (corresponding to 1416.7 and 1442 .5 cm(-1) in solid Ar, 1412.1 and 1440.7 cm(-1) in solid Kr) is discus sed. Temporal profiles of absorbance A(OClO) and A(ClOO) were probed a fter various periods of irradiation until approximately 20%-60% of OCl O was destroyed. Excitation of the nu(3) vibrational mode of OClO (A) over tilde (2)A(2) enhances photodissociation of OClO appreciably. Rat es of destruction of OClO in solid Ar or Kr are much smaller than that in solid Ne. The apparent conversion factor! Delta A(ClOO)/(- Delta A (OClO)) is greater for OClO in solid Ne than that in solid Ar or Kr. E ffects of matrix host on photolysis are discussed. (C) 1998 American I nstitute of Physics.