Temperature dependence of three-body association reactions from 45 to 400 K. The reactions N+2+2N2→N+4+N2 and O+2+2O2→O+4 +O2

Abstract

The temperature dependences of the three-body ion–molecule association reactions N+2+2N2→N+4+N2 (1) and O+2+2O2→O+4+O2 (2) have been studied in a recently constructed liquid-helium cooled ion drift tube in the temperature range 45–400 and 51–340 K, respectively. The results can be approximated over a wide temperature range by the expressions k1=6.8 × 10−29 (300/T)1.64 and k2=4 × 10−30 (300/T)2.93 although deviations at low temperatures are apparent. The influence of the electric drift field on the measured rate coefficients has been investigated in detail. Experimental effects which might be of importance in the low temperature measurements are discussed.