4343-68-4Relevant articles and documents
Direct measurements of the rate constants of the reactions NCN + NO and NCN + NO2 behind shock waves
Dammeier,Friedrichs
, p. 14382 - 14390 (2012/03/09)
The high-temperature rate constants of the reactions NCN + NO and NCN + NO2 have been directly measured behind shock waves under pseudo-first-order conditions. NCN has been generated by the pyrolysis of cyanogen azide (NCN 3) and quantitatively detected by sensitive difference amplification laser absorption spectroscopy at a wavelength of 329.1302 nm. The NCN 3 decomposition initially yields electronically excited 1NCN radicals, which are subsequently transformed to the triplet ground state by collision-induced intersystem crossing (CIISC). CIISC efficiencies were found to increase in the order of Ar 2 2 reactions can be expressed as kNCN+NO/(cm3 mol -1s-1) = 1.9 × 1012 exp[- 26.3 (kJ/mol)/RT] (±7%, ΔEa = ± 1.6 kJ/mol, 764 K NCN+NO2/(cm3 mol-1s -1) = 4.7 × 1012 exp[- 38.0(kJ/mol)/RT] (±19%,ΔEa = ± 3.8 kJ/mol, 704 K -6 mol/cm 3). For both reactions, the minima of the total rate constants occur at temperatures below 700 K, showing that, at combustion-relevant temperatures, the overall reactions are dominated by direct or indirect abstraction pathways according to NCN + NO f CN + N2O and NCN + NO2 → NCNO + NO. (Figure presented)