Abstract
Studies of time-resolved absorption spectra of transient species in the decomposition of NH3 by an r.f. pulse discharge together with product analysis showed that the major radical formed was NH at concentrations of the order of 10−6 mol dm−3 (105 molec. cm−3). Possible mechanisms for the formation of the radical during the discharge and its decay following pulse cut-off were tested by computer simulation of the kinetic data. Following zero-order formation with rate coefficient 0.19±0.03 mol dm−3 s−1, the decay was second order in NH with rate coefficient 2.1±0.5×109 mol−1 dm3 s−1 both for pure NH3 and where NH3/rare gas mixtures were investigated. The kinetic data are consistent with NH removal in a nonassociative radical-radical reaction proceeding via a short-lived collision complex, probably 2NH → N2H2 → N2 + H2.
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Nicholas, J.E., Spiers, A.I. & Martin, N.A. Kinetics and mechanism in the decomposition of NH3 in a radio-frequency pulse discharge. Plasma Chem Plasma Process 6, 39–51 (1986). https://doi.org/10.1007/BF00573820
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DOI: https://doi.org/10.1007/BF00573820