Theoretical and Experimental Chemistry

, Volume 24, Issue 2, pp 217–219 | Cite as

Spectroscopic manifestation of the accidental degeneracy of π=Δ electronic adiabatic terms of linear triatomic systems

  • L. V. Poluyanov
Brief Communications


The semiclassical form of the absorption band of a linear triatomic system which corresponds to an electronic transition from the Σ-ground state term to the excited intersection π and δ terms was calculated. The analysis was carried for negligibly small defect of frequencies and in the absence of a shift of the equilibrium position on excitation. The experimentally observed CuCl2 absorption spectrum was interpreted qualitatively as a π, Δ ← gS transition on the existence of a point of π=Δ accidental degeneracy. The 7000–24000 cm−1 energy interval in the spectrum was analyzed.


Absorption Spectrum Absorption Band Electronic Transition CuCl2 Equilibrium Position 


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Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • L. V. Poluyanov
    • 1
  1. 1.Division of the Institute of Chemical PhysicsAcademy of Sciences of the Soviet UnionMoscow

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