Chemical HF lasers from flash photolysis of various N₂F₄ + RH systems

HF stimulated emission has been observed from flash-photolyzed mixtures of N₂F₄ with a number of hydrogen sources: HCl, CH₄, CH₃F, CH₂F₂, CH₃Br, C₂H₆, C₂H₅F, and C₂H₅I. The vibrational-rotational transitions P₂₁(4)-P₂₁(8) and P₁₀(6)-P₁₀(9) were found in all cases examined with one exception. Under present conditions the emission is believed to result predominantly from the abstraction reaction F + RH → HF⁺ + R · Detailed analysis of the photoproducts indicates two other reactions yielding HF are occurring. The first has been recently studied by Padrick and Pimentel 1 R · + N₂F₄ → RNF₂⁺ + NF₂ RNF₂⁺ → R′CN + 2HF⁺ The second is a proposed new NF radical insertion-elimination reaction NF + RH → RNHF⁺ → HF⁺ + R′-CH=NH It is noted that uv photodissociation of NF₂ could yield metastable NF(¹Δ) radical.