Critical review of N, N, N, N , and N main production processes and reactions of relevance to titan's atmosphere

This paper is a detailed critical review of the production processes and reactions of N, N, N, N, and N of relevance to Titan's atmosphere. The review includes neutral, ion-molecule, and recombination reactions. The review covers all possible active nitrogen species under Titan's atmospheric conditions, specifically N (A Σ), N ( S), N ( D), N ( P), N, N ( P), N ( D), N, and N species, and includes a critical survey of the reactions of N, N, N, N , and N with N, H , D, CH, CH, C H, CH, CH and the deuterated hydrocarbon analogs, as well as the recombination reactions of N, N, N , and N. Production processes, lifetimes, and quenching by collisions with N of all reactant species are reviewed. The N ( S) state is reactive with radicals and its reactions with CH, CH, CH, and CH are reviewed. Metastable states N (A Σ), N ( D), and N ( P) are either reactive or quenched by collisions with the target molecules reviewed. The reactions of N ( D) have similar rate constants as N ( P), but the product branching ratios differ significantly. Temperature effects and the role of the kinetic energy content of reactants are investigated. In all cases, experimental uncertainties of laboratory data are reported or estimated. Recommended values with uncertainties, or estimated values when no data are available, are given for rate constants and product branching ratios at 300 K and at the atmospheric temperature range of Titan (150-200 K for neutral reactions and 150 K for ion reactions). © 2013. The American Astronomical Society. All rights reserved..