Dushinsky effect

Two modes of the same symmetry can mix under electronic excitation. This mixing, which can be depicted as a normal coordinate rotation, is known as the Dushinsky effect (Dushinsky, 1937). If the adiabatic ground-state potentials of the two modes, labeled j = and j = 2, are... 

To this end, harmonic vibrational frequencies for both So and states were determined using density functional theory at the B3LYP level and SVP basis sets. The Franck-Condon factors were determined taking full account of mode mixing effects (Dushinsky rotation) [143]. 

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