Chemiluminescent Emission of CO Fourth Positive Bands in Nitrogen Atom/Oxygen Atom/Reactive Carbon Compound Systems. Relation to Chemihyphen;ionization

摘要

Emission of the CO Fourth Positive Bandslpar;A1pgr;ndash;X1Sgr;plus;rpar;is observed in the reactions of atomic N/O mixtures with C2F4, C2H4, C2H2, and C2N2at about 300deg;K and pressures of 1ndash;4 Torr. The N/O/C2F4system, which has been investigated most extensively, produces COA1pgr;ndash;X1Sgr;plus;emission which, like the NOplus;chemihyphen;ion formation rate, follows N3O kinetics. The level of excitation extends to at least 10.3 eV aboveCOlpar;X1Sgr;plus;, ugr;thinsp;equals;thinsp;0rpar;. It is shown that the formation ofCOlpar;A1pgr;rpar;can be attributed to enhanced formation of excited N2and NO molecules in atomhyphen;recombination reactions induced by a reaction intermediate (probably CN), followed by pooling of the energy of an N2* and an NO* molecule and energy transfer to the reaction productCOlpar;X1Sgr;plus;rpar;. The transfer reaction can take place before or after the pooling reaction. Formation ofCOlpar;A1pgr;rpar;in the N/O/C2H4system exhibits the same kinetic dependence on N and O atoms. For the N/O/C2H2system, the observations indicateCOlpar;A1pgr;rpar;formation both via the above energyhyphen;pooling mechanism and via the mechanism operative in the O/C2H2reaction Oplus;C2Orarr;CO(A1pgr;)plus;CO(X1Sgr;plus;). In the N/O/C reactions, the higher vibrational levels ofCOlpar;A1pgr;rpar;are relatively more populated than in the O/C2H2reaction.