Low temperature rate coefficients for vibrational relaxation of 3Σ+u Rb2 molecules by 3He and 4He atoms

Alexandra Viel (1) , Jean-Michel Launay (1)

1 IPR - Institut de Physique de Rennes

We present quantum scattering calculations of 4 He and 3 He colliding with 87 Rb 2. For both helium isotopes, the elastic and inelastic rate coefficients are strongly influenced by the J = 1 partial wave. For the lighter isotope a strong resonance feature of the J = 1 partial wave is responsible for an extremely efficient vibrational relaxation process. We also perform bound-state calculations of the Rb 2 He complex for even Rb permutation symmetry and non-zero total angular momentum. The global Rb 2 He 3 Σ + u potential energy surface used supports four bound states for 4 He and a single one for 3 He. We propose an analysis of the 87 Rb 2 4 He spectrum separating the contributions of Rb 2 rotation and helium motion.

Keywords: Quantum dynamics; Atomic and molecular collisions; Molecular physics; Cold and ultra-cold collisions; Spectral element methods

Domains: Physics [physics]; Physics [physics]; Chemical Physics [physics.chem-ph]; Physics [physics]; Quantum Physics [quant-ph]; Physics [physics]; Physics [physics]; Computational Physics [physics.comp-ph]

Alexandra Viel, Jean-Michel Launay. Low temperature rate coefficients for vibrational relaxation of 3Σ+u Rb2 molecules by 3He and 4He atoms. Journal of Physical Chemistry A, 2014, 118 (33), pp.6529-6535. ⟨10.1021/jp503086b⟩. ⟨hal-00988039⟩