Theoretical study of Rb2 in He(N): potential energy surface and Monte Carlo simulations.

Grégoire Guillon (1) , Alexandre Zanchet (1, 2) , Markku Leino (1) , Alexandra Viel (1) , Robert E Zillich (3)

1 IPR - Institut de Physique de Rennes
2 CSIC - Insituto de Física Fundamental
3 Institute for Theoretical Physics

An analytical potential energy surface for a rigid Rb₂ in the ³Σ(u)⁺ state interacting with one helium atom based on accurate ab initio computations is proposed. This 2-dimensional potential is used, together with the pair approximation approach, to investigate Rb₂ attached to small helium clusters He(N) with N = 1-6, 12, and 20 by means of quantum Monte Carlo studies. The limit of large clusters is approximated by a flat helium surface. The relative orientation of the dialkali axis and the helium surface is found to be parallel. Dynamical investigations of the pendular and of the in-plane rotation of the rigid Rb₂ molecule on the surface are presented.

Mots clés: Molecular physics; Quantum Monte Carlo; Helium clusters; Quantum dynamics

Domaines: Physique [physics]

Grégoire Guillon, Alexandre Zanchet, Markku Leino, Alexandra Viel, Robert E Zillich. Theoretical study of Rb2 in He(N): potential energy surface and Monte Carlo simulations.. Journal of Physical Chemistry A, 2011, 115 (25), pp.6918-6926. ⟨10.1021/jp112053b⟩. ⟨hal-00700162⟩