Hydrogen Fluoride Elimination Chemical Laser from N,N-Difluoromethylamine

Abstract

Hydrogen fluoride laser emission has been observed following flash photolysis of mixtures of CH₄+N₂F₄ and CH₃I+N₂F₄. Both N₂F₄ and NF₂ were found to be good sources of fluorine atoms to cause HF laser emission through H‐atom abstraction. At temperatures below 268°K and with photolysis occurring in a Vycor laser tube, F‐atom production was reduced to the point that no emission was observed in the N₂F₄+CH₄ system. However, emission was still observed in the CH₃I+N₂F₄ system and was attributed to the following reactions: $${\mathrm{CH}}_3\mathrm{I}\to {\displaystyle {lim}^{\mathrm{h\nu }}}{\mathrm{CH}}_3+\mathrm{I}\mathrm{*,}$$ $${\mathrm{CH}}_3+{\mathrm{N}}_2{\mathrm{F}}_4\to {\mathrm{CH}}_3{\mathrm{NF}}_2^{†}+{\mathrm{NF}}_2,$$ $${\mathrm{CH}}_3{\mathrm{NF}}_2^{†}\to \mathrm{HCN}\text{+2}{\mathrm{HF}}^{†}.$$ At 248°K, emission was observed in only two transitions $P_{\text{1→0}}\text{(5)}$ and $P_{\text{1→0}}\text{(6)}$ . The population ratio $N_1{\mathrm{\hspace{0.17em}/\hspace{0.17em}N}}_0$ has been found to be in the range 0.33–0.37 for the elimination reaction, the lowest yet recorded for a chemical laser.