Kinetics of Gas Phase Ion-Ion Recombination in NO++X- ->NO+X for X being Chlorine, Bromine and Iodine

Abstract

The rate coefficient for the gas phase recombination of N0+ with halide ions X- in NO++X-->NO+X has been measured in flames of C2H2 + O2 + N2 over the temperature range 2200 to 2650 K. Chlorine, bromine and iodine have been used as X. All At values are in the range 0.8-2.lx 10~8 ion -1 cm3 s-1, corresponding to cross-sections (tto2) of ~10-17 m2. For each halogen, ki has a negative temperature coefficient. Also at any one temperature, kt is largest for X being chlorine and smallest for iodine. In general, these measurements are in agreement with Olson’s “ absorbing sphere ” model for ion-ion recombination.