Rate coefficients for N +2( ν) dissociative recombination

Abstract

The data of Zipf (1980; Geophys. Res. Lett. 7, 645) on N + 2( ν) dissociative recombination are analysed taking into account that, as Johnsen (1987 ; Mass Spectrosc. Ion Process. 81, 67) has pointed out, there is coupling due to symmetrical resonance charge transfer, N + 2( ν) + N 2(0)N + 2(0) + N + 2( ν), and taking into account the vibrational deactivation in N + 2( ν)-Ne collisions. A reported experimental value of the vibrational deactivation coefficient is much higher than would be expected or than can be reconciled with the results of Zipf and it is therefore rejected. The analysis shows that the recombination coefficient for N + 2(0) is about 2.6×10 −7 cm 3 s −1 at 300 K and that the recombination coefficients for N + 2(1) and N + 2(2) are considerably smaller. These coefficients conflict with the dissociative recombination cross section vs energy curve obtained by the merged beam method. Reasons are given for believing that the curve cannot be correct.