Coupling of Bound States to Continuum States in Neutral Triatomic Hydrogen

  • H. Helm
  • U. Galster
  • I. Mistrík
  • U. Müller
  • R. Reichle


Rydberg states of the neutral triatomic hydrogen molecule can be viewed as an electron attached to a tightly bound H 3 + core.1–4 These states are embedded in the dissociation continuum of the repulsive electronic ground state surface as seen from Fig. 1. As a consequence, all excited bound states of H3 are subject to predissociation. The metastable 2pA2″(N=K=0) state is a notable exception. Here N refers to the total angular momentum apart from spin and K to the projection of N on the molecular top axis. This lowest rotational level is long-lived (700 ns)5 owing to symmetry forbidden coupling with the electronic ground state by either radiation or predissociation. Neutral H3 in this rotational level can be selectively prepared in a fast beam by charge exchange techniques. This state has been used as a platform for laser-excitation experiments3–14 to explore the structure and dynamics of highly excited states of H3.


Potential Energy Surface Rydberg State Dalitz Plot Dissociative Recombination Rydberg Electron 
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Copyright information

© Springer Science+Business Media New York 2003

Authors and Affiliations

  • H. Helm
    • 1
  • U. Galster
    • 1
  • I. Mistrík
    • 1
  • U. Müller
    • 1
  • R. Reichle
    • 1
  1. 1.Department of Molecular and Optical PhysicsUniversität Freiburg, Fakultät für PhysikFreiburgGermany

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