Quenching of vibrationally excited molecules by collisions with ions: controlling the scattering via

Inducing low-energy p-wave resonances by an additional external electric field has been shown recently to be a possible way of controlling ultra-low energy atomic collisions (Krems R. V., Phys. Rev. Lett., 96 (2006) 123202). We show here by calculation that also in molecular systems with long-range interactions there exist internal states for which a low energy p-wave resonance is clearly contributing to the scattering even at ultra-low energies, and that for this collisional regime the scattering length turns out to be positive. We thus present results for the vibrational relaxation cross-sections of H 2, prepared in different vibrational states, in collision with Li+ in that energy regime and examine the changes in scattering attributes, both in the elastic and inelastic channels, when the internal vibrational state of H2 is modified. Copyright © EPLA, 2007.