Torsional and rotational couplings in nonrigid molecules

  title={Torsional and rotational couplings in nonrigid molecules},
  author={Juan J. Omiste and Lars Bojer Madsen},
  journal={Physical Review A},
We analyze theoretically the interplay between the torsional and the rotational motion of an aligned biphenyl-like molecule. To do so, we consider a transition between two electronic states with different internal torsional potentials, induced by means of a resonant laser pulse. The change in the internal torsional potential provokes the motion of the torsional wavepacket in the excited electronic state, modifying the structure of the molecule, and hence, its inertia tensor. We find that this… 

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