Electronic states distorted configurations, nondegenerate

Our model system will be a molecule with three electronic levels. The electronic ground state is taken to be nondegenerate. The two excited electronic states are Jahn-Teller active, being degenerate at the symmetrical nuclear configuration and coupled by distortion of the molecule away from the symmetrical configuration. The symmetric shape corresponds to values <7, = 2 0 of the two internal coordinates. We suppress... 

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