Herzberg–Teller Vibronic Coupling and the Duschinsky Effect

摘要: The assumption that the difference in composition, terms of symmetry coordinates, between normal vibrational motions ground and first excited state (Duschinsky effect) can be neglected Herzberg–Teller theory absorption fluorescence vibronic intensities is critically examined. A Duschinsky effect described which involves expansion potential energy fluorescent coordinate displacements. Off‐diagonal quadratic contributions arise whenever there a coupling crude Born–Oppenheimer electronic wavefunctions other states through two or more same symmetry. importance depends on magnitudes matrix elements frequency differences fundamentals perturbations. Inclusion theor...