Abstract

A high power pulsed CO_2 laser was used to induce reactions in gas mixtures containing either N_2F_4 or SF_6. The rate of laser induced dissociation of N_2F_4 to NF_2 was as much as 1000 times faster than the thermal rate, and the rate law was of lower order than the thermal, bimolecular rate law. Explosion threshold and induction time data were obtained for butene stabilized mixtures of N_2F_4 and H_2. HF laser gain was observed during the first few microseconds of CO_2 laser pulse, but it was strongly quenched by the explosion. The laser driven reaction of SF_6 with H_2 also exhibited HF laser gain at early times and laser energy threshold for reaction. All of the laser induced reactions studied occurred at rates that were faster than the rates of thermal reaction. This accelerated reaction rate was attributed to nonthermal vibrational excitation of the reactants. A computer model of the SF_6-H_2 electrical discharge chemical laser was employed to gain a better understanding of the fundamental processes that occur in this laser. Good agreement with experimental results were obtained, and several suggestions for further study were made.

Degree

PhD

College and Department

Physical and Mathematical Sciences; Chemistry and Biochemistry

Rights

http://lib.byu.edu/about/copyright/