Experiments of Multiphoton Dissociation and Ionization of Molecules

  • H. Rottke


The field of multiphoton dissociation and ionization of molecules is extremely broad. Therefore I will restrict myself to an introduction into experimental investigations on strong field light—molecule interaction, present some of the main experimental results, and their implications on the understanding of the interaction. Strong means that the electric field strength of the light wave becomes comparable to the intramolecular Coulomb interaction, which binds electrons in the valence shell and is responsible for molecular bonding. The electric field strengths of interest will be in the range from E 0 ≈ 1010 V/m to E 0 ≈ 1012 V/m. According to the relation
$$ I = \frac{1}{2}\sqrt {\frac{{{ \in _0}}}{{{\mu _0}}}} E_0^2 $$
between the electric field strength and the intensity I of a light wave the corresponding intensity ranges from I ≈ 1013 W/cm2 up to I ≈ 1017 W/cm2. At these light intensities the light—molecule interaction can no longer be analysed theoretically by perturbation methods. Nevertheless, it will be shown that even in this extreme situation quite simple physical mechanisms have been found which enable one to understand excitation and fragmentation of a molecule. Partly, these mechanisms are not molecule specific but apply generally to molecules.


Momentum Distribution Double Ionization Coulomb Explosion Kinetic Energy Distribution Internuclear Separation 
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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • H. Rottke
    • 1
  1. 1.Max-Born-InsitutBerlin-AdlershofGermany

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