infrared laser decomposition of propane photosensitized by sulfur hexafluoride

in recent years an abundance of theoretical and experimental works concerning infrared photochemistry has been accomplished. it coincides with the possibility of using intense infrared laser radiation to dissociate molecules in order to induce a selective laser photochemistry. however, the major fraction of these works is concerned with the pulsed photolysis in order to minimize the temperature effect following necessarily the absorption of intense radiations. moreover it allows to dispose of extremely high and quasi instantaneous photonic densities in collisionless conditions. however ,the pulsed technique overlooks some specific photophysical and photochemical features related to the coupling between a polyatomic molecule and a continuous strong i.r. field. on this connection, we have studied the hydrocarbon decomposition in presence of a beam issued from a c.w. co laser at 10.6 µ m, this hydrocarbon ordinarily transparent must be photosensitized by sf . the photosensitizing (q.s.s. ) conditions have been described elsewhere and the gaseous mixtures are exposed upon unfocused irridiation with time ranging from 0 to 1 second, at changing hydrocarbon pressure and fixed sf6 pressure ( 3.3 torrs ) . this paper is dealing with a comparison between some photophysical , photochemical and photokinetic aspects of the