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Updated: Mar 11, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Comparative experimental and theoretical study of the rotational excitation of CO by collision with ortho- and
T Stoecklin1, A Faure2, P Jankowski3
1Univ. Bordeaux, ISM, UMR 5255, F-33400 Talence, France. thierry.stoecklin@u-bordeaux.fr and CNRS, ISM, UMR 5255, F-33400 Talence, France.
Abstract:
A joint crossed beam and quantum mechanical investigation of the rotationally inelastic collisions of CO with ortho- and para-D2 molecules is reported. A new 4D potential energy surface (PES) averaged over the ground vibrational states of D2 and CO is used to calculate the rovibrational bound states of the ortho-D2-CO complexes. Close coupling calculations are then performed in the rigid rotor approximation for ortho- and para-D2 colliding with CO for the experimentally investigated transition of CO (j = 0 → 1) and for collision energies ranging from 0.1 to 25 cm-1. The agreement between theory and experiment is found to be very good for both the bound state energies of the ortho-D2-CO complexes and for the inelastic scattering cross-sections showing that the free rotation of two rigid rotors is a very good model of the D2-CO system in this low collision energy domain.
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