Abstract: Active nitrogen has been prepared by hollow-cathode discharge of N₂ in a flowing afterglow system. Strong emission spectra of NBr(b¹Σ⁺→X³Σ^-) have been observed when alkyl bromides (CHBr₃, CH₂Br₂, C₂H₅Br, C₄H₉Br) are added to a stream of active nitrogen. In addition, weak CN(A²π, B²π→X²Σ⁺) emission spectra have been detected only in the case of CHBr₃ or CH₂Br₂ as reagents. Some tentative experiments show that the electronically excited NBr(b¹Σ⁺) is formed by mechanism of metastable N₂(A³Σ_u⁺) electronic-to-electronic energy transfer from ground state NBr(X³Σ^-), which is from the reaction of N(⁴S) with alkyl bromides. The excited CN (A²π, B²π) comes from the reaction of N(⁴S) with CBr formed due to CHBr₃(or CH₂Br₂) dissociation by N₂(A³Σ_u⁺).

Key words: Active nitrogen, Energy transfer, Emission spectra, NBr, CN