VUV fluorescence following photodissociation of N2O at 193 nm

摘要

Photolytic studies performed at 193 nm demonstrate that NO in the highly excitedD(v= 1,5) andE(v= 0) states is generated from N2O during irradiation in three sequential steps involving photodissociation, chemical reaction, and photoexcitation. The resulting NO fluorescence (160ndash;230 nm) was analyzed with a system of rate equations, and the temporal behavior, intensity dependence, and pressure dependence were found to be consistent with a simple kinetic model. The quenching coefficient of NO by N2, Ar, and N2O were determined in this analysis to beqN2= (2.7plusmn;0.8)times;10minus;11cm3thinsp;secminus;1,qAr= (6.6plusmn;1.4)times;10minus;11cm3thinsp;secminus;1, andqN2O= (1.5plusmn;0.4)times;10minus;10cm3thinsp;secminus;1. Finally, dramatic changes in the spectral distribution of the ultraviolet NO fluorescence due to collisions with He were observed, which contrasts with the absence of spectral redistribution in collisions involving N2, Ar, and N2O.