Classification and normal forms for avoided crossings of quantum-mechanical energy levels

@article{Hagedorn1998ClassificationAN,
  title={Classification and normal forms for avoided crossings of quantum-mechanical energy levels},
  author={George A. Hagedorn},
  journal={Journal of Physics A},
  year={1998},
  volume={31},
  pages={369-383}
}
  • G. Hagedorn
  • Published 9 January 1998
  • Physics
  • Journal of Physics A
When using the Born-Oppenheimer approximation for molecular systems, one encounters a quantum mechanical Hamiltonian for the electrons that depends on several parameters that describe the positions of the nuclei. As these parameters are varied, the spectrum of the electron Hamiltonian may vary. In particular, discrete eigenvalues may approach very close to one another at `avoided crossings' of the electronic energy levels. We give a definition of an avoided crossing and classify generic avoided… 

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This is the second of two papers on the propagation of molecular wave packets through avoided crossings of electronic energy levels in a limit where the gap between the levels shrinks as the nuclear

Classification and normal forms for quantum mechanical eigenvalue crossings

© Société mathématique de France, 1992, tous droits réservés. L’accès aux archives de la collection « Astérisque » (http://smf4.emath.fr/ Publications/Asterisque/) implique l’accord avec les

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Nous etudions la propagation de paquets d'ondes moleculaires au travers des deux types les plus simples de croisements evites de niveaux d'energie electroniques, dans la limite ou le gap entre ces

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