Chemiluminescent reactions in photodissociated cyanogen-oxygen mixtures

F/sub 2/ (158 nm) and ArF (193 nm) excimer radiation have been used to photodissociate C/sub 2/N/sub 2/ and produce chemiluminescence in C/sub 2/N/sub 2/-O/sub 2/ mixtures. In addition, LIF measurements have followed the temporal behavior of the CN and NCO radicals. The behavior of CN is understood in terms of its reactions with O/sub 2/ and O. The NCO decay is controlled by radical or atom intermediates. This study was focused on the NO ..gamma..-band chemiluminescence, and evidence is presented to support the view that it arises from energy transfer from N/sub 2/(A) to NO and the N/sub 2/(A) is made by the reaction N(/sup 2/D) + NCO ..-->.. N/sub 2/(A) + CO. An estimate of approx. = 25% is obtained for the N/sub 2/(A) yield of this reaction.