Dynamics in Polyatomic Molecules

Seel, M., and Domcke, W. (1991), Femtosecond Time-resolved Ionization Spectroscopy of Ultrafast Internal-Conversion Dynamics in Polyatomic Molecules Theory and Computational Studies, J. Chem. Phys. 95,7806. 

TIME-RESOLVED PHOTOELECTRON SPECTROSCOPY OF NONADIABATIC DYNAMICS IN POLYATOMIC MOLECULES... 

The most illuminating consequence of multi-dimensional vibrational dynamics in polyatomic molecules are fluctuations of resonance widths. In particular, narrow resonances can often be found far above the first dissociation threshold. We have seen that in systems with one degree of freedom the sequence of resonance states is rather short. Since the excitation energy is deposited directly into the reaction coordinate, the complex breaks apart very quickly and the resonances become broad even close to the dissociation threshold. In polyatomic molecules, energy can be temporarily stored in additional degrees of freedom. The lifetime is then determined not only by the total energy, but also by the rate with which the excitation can be redistributed and transferred to the dissociation bond (see the discussion of the classical phase space structure in Sect. 8). 

This attractive feature makes this class of control mechanisms a promising candidate for the laser control of non adiabatic dynamics in polyatomic molecules. Despite this, much work will be necessary to further assess the applicability of control mechanisms based on the Stark effect to a wide class of systems. 

Natural Orbitals Nonadiabatic Derivative Couplings Photochemistry Photodissociation Dynamics Valence Bond Curve Crossing Models Vibronic Dynamics in Polyatomic Molecules. 

Electronic Diabatic States Definition, Computation, and Applications Gradient Theory Photochemistry Photodisso ciation Dynamics Vibronic Dynamics in Polyatomic Molecules. 

Classical Dynamics of Nonequilibrium Processes in Fluids Integrating the Classical Equations of Motion Control of Microworld Chemical and Physical Processes Mixed Quantum-Classical Methods Multiphoton Excitation Non-adiabatic Derivative Couplings Photochemistry Rates of Chemical Reactions Reactive Scattering of Polyatomic Molecules Spectroscopy Computational Methods State to State Reactive Scattering Statistical Adiabatic Channel Models Time-dependent Multiconfigurational Hartree Method Trajectory Simulations of Molecular Collisions Classical Treatment Transition State Theory Unimolecular Reaction Dynamics Valence Bond Curve Crossing Models Vibrational Energy Level Calculations Vibronic Dynamics in Polyatomic Molecules Wave Packets. 

Having introduced the basic concepts and numerical techniques, we briefly discuss representative examples of vibronic dynamics in polyatomic molecules. These serve to illustrate key features of relevant obsei-vables and also the type of... 

Weakly bound systems from van der Waals to strong hydrogen bonds are treated theoretically in ECC in the article by Bogumil Jeziorski Intermolecular Interactions by Perturbation Theory). Related articles are those of Tucker Carrington Vibrational Energy Level Calculations), Wolfgang Domcke Vibronic Dynamics in Polyatomic Molecules), and of Martin Quack Multiphoton Excitation). 

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