vibronic coupling

The vibronic coupling in this approach is through nuclear kinetic energy terms.

The evaluation of vibronic coupling often involve complex mathematical treatment.

In general, the potential energy surfaces are coupled via the vibronic coupling terms.

As a result, direct evaluation of vibronic couplings are mostly limited to very small molecules.

As a result, few programs have currently implemented analytic evaluation of vibronic couplings.

The direct calculation of vibronic couplings is not common due to difficulties associated with its evaluation.

Perhaps the earliest examples of the importance of vibronic coupling were found during the 1930s.

The form of vibronic coupling is essentially derivative of the wave function.

Vibronic coupling describes the mixing of different electronic state as a result of small vibrations.

This is further complicated by the fact that definition of vibronic couplings requires electronic wavefunctions.

At the same time we will show how the BO approximation may be improved by including vibronic coupling.

As a result, the algorithms to evaluate vibronic couplings are not yet implemented in many quantum chemistry program suits.

Resonance Raman spectroscopy involves a kind of vibronic coupling.

The coupling terms are called vibronic couplings.

The vibronic coupling acts as a perturbation.

Evaluation of vibronic couplings is often associated with severe difficulties in mathematical formulation and program implementations.

The magnitude of vibronic coupling is often introduced as an empirical parameter determined by reproducing experimental data.

Therefore it cannot be used to correct wave-function-dependent quantities such as dipole moment, charge density and vibronic couplings.

In theoretical chemistry, the vibronic coupling is neglected within the Born-Oppenheimer approximation.

Although crucial to the understanding of nonadiabatic processes, direct evaluation of vibronic couplings has been very limited.

The evaluation of vibronic couplings also requires correct description of at least two electronic states in regions where they are strongly coupled.

Vibronic couplings are crucial to the understanding of nonadiabatic processes, especially near points of conical intersections.

In either case the adiabatic or Born-Oppenheimer approximation fails and vibronic couplings have to be taken into account.

The energies are determined by the shape of the molecular potential energy surfaces, the masses of the atoms, and the associated vibronic coupling.

At this point the very large vibronic coupling induces a non-radiative transition (surface-hopping) which leads the molecule back to its electronic ground state.