Isotopically selective IR multiphoton dissociation of CF3I molecules in a pulsed gasdynamic flow

An investigation was made of isotopically selective IR multiphoton dissociation of CF₃I molecules in a pulsed gasdynamic flow. The dependences of the C₂F₆ product yield on the energy density of the exciting laser radiation, on the CF₃I pressure above a nozzle, and on the number of pulses were obtained. The dependence of the ¹³C content in C₂F₆ on the exciting radiation frequency was also found. The conditions for dissociation of molecules optimal in respect of the C₂F₆ yield and the enrichment factor were identified. It was established that the C₂F₆ yield fell strongly on reduction of the CF₃I concentration in the flow, which was related to the loss of the product CF₃ radicals at the walls. The use of a low-pressure buffer (acceptor) gas, in the chamber where the molecular flow was formed, reduced the radical losses and increased the product yield.