PREDICTING THE NIGHTTIME NO3 RADICAL REACTIVITY IN THE TROPOSPHERE

A statistically significant linear correlation between the reaction, kNO, for the NO3 free radical reaction with 69 organic compounds in the gas phase at 298 K and the corresponding vertical ionization energies, Ei,v, allows an a priori prediction to be made of hitherto not measured compounds. With these reaction rate constants and a mean concentration of NO3 during the night, the upper limit of the tropospheric half-life of organic compounds and their persistence in the troposphere can be estimated. From the fairly good linear correlation between kNO and kOH it can be deduced that in the gas phase both free radicals react in a very analogous manner with organic compounds. © 1990.