VIBRATIONAL DISTRIBUTION IN CN(X-2-SIGMA(-2-]CN+C REACTION()) FROM THE N+C)

C-2 radicals were prepared from the overall reaction 4K + C2Cl4 --> 4K Cl + C-2 and mixed with atomic nitrogen in a low-pressure fast-flow re actor. CN(X-2 Sigma(+)) produced by the exoergic reaction N + C-2 --> CN + C was probed by laser-induced fluorescence. Vibrational distribut ions at different distances from the reactant mixing zone were determi ned. Fitting of the evolution of the vibrational distribution, using a kinetic scheme which included the collisional transfer between X-2 Si gma(+) and A(2)II(i) vibrational levels and CN removal by the N + CN - -> C + N-2 reaction, allowed to determine the nascent vibrational dist ribution given by the N + C-2 reaction. This distribution was found to be non-statistical and is compared to that obtained from the C + NO - -> CN + O reaction in a previous crossed-beam study. (C) 1997 Elsevier Science B.V.