Quenching rate constants of excited states of N2 and N2+ in interaction with hydrocarbons

We report results of studies of luminescence decay processes in excited states of nitrogen molecules and ions in gas mixtures with hydrocarbon molecules. Use is made of emission spectroscopy methods to perform measurements. Nitrogen molecules N₂ and nitrogen molecular ions N₂⁺ are excited to the C³ Π_u state and the B₂Σ⁺_u state, respectively, by a repeated high-voltage nanosecond discharge in the gas mixture in question. As a result of processing the data obtained by varying the composition of the gas mixtures and their pressure (1–20 Torr), the quenching rate constants of the excited states of nitrogen N₂(C³ Π_u) and N₂⁺(B₂Σ⁺_u) and in collisions with hydrocarbon molecules CH₄, C₂H₆, and C₃H₈ are determined. For the first time, the values of the quenching rate constants are obtained for a mixture of nitrogen and propane, as well as for the 3 → 7 transition of the emission band system N₂(C³ Π_u→B³ Π_g) of a nitrogen–methane mixture.