Two-body mutual neutralization rates of O2++ O−, NO++ O−, and Na++ O−obtained with merged beams

Two-body ion-ion neutralization rates have been measured by the merged beam technique for O2+ + O−, NO+ + O−, and Na+ + O− at well-defined energies in the range 0.15 to 20 ev. At barycentric energies above 1 ev, the rates are relatively constant and have respective values of about 6 × 10−8, 12 × 10−8, and 5 × 10−8 cm³/sec. For energies below 1 ev, the rates rise monotonically as is typical for these reactions. The data have been extrapolated to lower energies and averaged over a Boltzmann energy distribution to yield thermal reaction rates at 300° K of (10 ± 4) × 10−8, (49 ± 20) × 10−8, and (21 ± 10) × 10−8 cm³/sec for O2+ + O−, NO+ + O−, and Na+ + O−, respectively.