THE METHOD OF ELECTRONIC CHEMICAL ACTIVATION TO STUDY THE HYDRAZINE DECOMPOSITION VIA THE ELEMENTARY REACTION OF NH(A1-DELTA,UPSILON'' = 0,1) WITH NH3(X)OVERT-TILDE

The elementary reaction of NH(a 1DELTA, upsilon'' = 0,1) with ammonia NH(a 1DELTA, upsilon'' = 0,1) + NH3 --> N2H4 not-equal --> products was studied at room temperature in the gas phase at low pressure (p = 20 mbar). NH(a) was produced by HN3 laser photolysis (AL = 248 nm) and detected by laser induced fluorescence. Time resolution was obtained from the variable delay between the photolysis pulse and the detecting laser pulse. The rate constants were found to be: k1(upsilon'' = 0 = (8.99 +/- 0.9) . 10(13) cm3/mol s;k1(upsilon'' = 1) = 8.7 +/- 1.3) . 10(13) cm3/mol s, independent of the vibrational state of NH(a). The product NH2(X) and the quenching pathway [NH(X)] were followed directly and quantitatively by laser induced fluorescence. [NH2(X)] was calibrated with respect to [NH(a)]. The quenching pathway was found to be unimportant ([NH(X)]infinity/[NH(a)]0 < 1%). The chemical channel NH(a) + NH3 --> N2H4 not-equal --> 2NH2(X) was with (93 +/- 15)% the main reaction pathway.