Anomalous vibrational excitation of O2in collisions with protons at 10 eV when compared with N2, CO and NO

Abstract
Structured time-of-flight spectra of protons scattered from O2 have been measured at scattering angles 5 degrees cmcm=9.5 eV. A comparison with similar measurements for N2, CO and NO reveals a factor of three greater vibrational energy transfer and roughly a factor of two less rotational energy transfer. On the basis of molecular orbitals an explanation involving a charge transfer mechanism is presented for the enhancement of vibrational excitation in O2.