Quenching of vibrationally excited molecules by ultracold collisions with ions: Controlling the scattering via changes of internal statesE. Bodo and F. A. Gianturco
Dipartimento di Chimica and CNISM, Università di Roma "La Sapienza" - P.le A. Moro 5, 00185, Roma, Italy
received 16 October 2006; accepted in final form 29 November 2006; published February 2007
published online 1 February 2007
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 H2, prepared in different vibrational states, in collision with 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.
34.50.Lf - Chemical reactions, energy disposal, and angular distribution, as studied by atomic and molecular beams .
34.20.Mq - Potential energy surfaces for collisions.
© Europhysics Letters Association 2007