KINETICS OF CHEMICALLY PUMPED NF(B1-SIGMA+) - STUDY OF NF(A1-DELTA)+I-ASTERISK(P-2(1/2)) -] NF(B1-SIGMA+) +I(P-2(3/2)) ENERGY POOLING

The fast, near-resonant energy pooling between electronically excited NF(a1DELTA) and (I*(P1/2))-P-2 to form NF(b1SIGMA+) has been investigated at 448 K using pulsed I* laser optical pumping. These reagents were obtained from 193-nm photolysis of HI in the presence of NF2 and buffer gas mixtures. During the saturating I* laser pulse, analysis of the NF(b1SIGMA+) time profiles is simplified due to the clamping of the ([I*(P1/2)])-P-2/([1(P3/2)])-P-2 ratio. Direct determinations of the rate coefficients for NF(a1DELTA) +(I*(P1/2)-P-2) --> NF(b1SIGMA+) + (I(P3/2)-P-2) [(5 +/- 2) X 10(-11) cm3/(molecule s)] energy transfer and for the reaction between NF(b1SIGMA+) and (I*(P3/2)-P-2) [(1.2 +/- 0.5) x 10(-10) cm3/(molecule s)] are presented. Also reported are rate coefficients for the NF(b1SIGMA+) +(I(P3/2)-P-2) --> NF(a1DELTA) + (I*(P1/2)-P-2) [(3.1 +/- 1) X 10(-11) CM3/(Molecule s)] and NF(b1SIGMA+) + (I(P3/2)-P-2) --> other products [(8.8 +/- 4.4) x 10(-11) cm3/(molecule s)] reactions.