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