Wave packet dynamics

Dey B D, Askar A and Rabitz H 1998 Multidimensional wave packet dynamics within the fluid dynamical formulation of the Schrddinger equation J. Chem. Phys. 109 8770-82... 

Molecular spectroscopy offers a fiindamental approach to intramolecular processes [18, 94]. The spectral analysis in temis of detailed quantum mechanical models in principle provides the complete infomiation about the wave-packet dynamics on a level of detail not easily accessible by time-resolved teclmiques. 

Figure 4, Control of wave packet dynamics in an optimal 5-well structure. The parameters of the structure are designed to maximize tunneling. The wave packet at the target time (solid line) has a large overlap with the target (dashed line).

Daniel C (2004) Electronic Spectroscopy and Photoreactivity of Transition Metal Complexes Quantum Chemistry and Wave Packet Dynamics. 241 119-165... 

There are two issues that may be confusing in the development above. The first issue, which applies to any/(H), including simply/(H) = H, is how to obtain correct scattering dynamics information if only the real part of the wave packet is available. The second issue is the relation of the wave packet dynamics generated by the/(H) of choice in the RWP method, Eq. (16), to standard wave packet dynamics generated by H. That is, can % u) be related to T(f) in a more explicit manner than in the discussion revolving around Eqs. (13) and (14) ... 

QUANTUM DYNAMICS OF CHEMICAL REACTIONS we can relate to wave packet dynamics under/(//) ... 

A typical initial condition in ordinary wave packet dynamics is an incoming Gaussian wave packet consistent with particular diatomic vibrational and rotational quantum numbers. In the present case, of course, one has two diatomics and with the rotational basis representation of Eq. (30) one would have, for the full complex wave packet. 

To obtain a first impression of the nonadiabatic wave-packet dynamics of the three-mode two-state model. Fig. 34 shows the quantum-mechanical probability density P (cp, f) = ( (f) / ) (p)(cp ( / (f)) of the system, plotted as a function of time t and the isomerization coordinate cp. To clearly show the... 

All approaches for the description of nonadiabatic dynamics discussed so far have used the simple quasi-classical approximation (16) to describe the dynamics of the nuclear degrees of freedom. As a consequence, these methods are in general not able to account for processes or observables for which quantum effects of the nuclear degrees of freedom are important. Such processes include nuclear tunneling, interference effects in wave-packet dynamics, and the conservation of zero-point energy. In contrast to quasi-classical approximations, semiclassical methods take into account the phase exp iSi/h) of a classical trajectory and are therefore capable—at least in principle—of describing quantum effects. 

M. Rosina and R Van Leuven, Density-matrix approach to wave-packet dynamics. Phys. Rev. A 45, 64-69 (1992). 

Fig. 4. Cr(CO)s excited state relaxation dynamics comparison of semi-classical trajectory surface hopping (left), and MCTDH wave packet dynamics (right). Trajectory shows molecule passing through TBP Jahn-Teller geometry within 130 fs, then oscillating in SP potential well afterward. Wave packet dynamics plotted for the Si and S0 adiabatic states in the space the symmetric and asymmetric CCrC bending coordinates.

Each of the semi-classical trajectory surface hopping and quantum wave packet dynamics simulations has its pros and cons. For the semi-classical trajectory surface hopping, the lack of coherence and phase of the nuclei, and total time per trajectory are cons whereas inclusion of all nuclear degrees of freedom, the use of potentials direct from electronic structure theory, the ease of increasing accuracy by running more trajectories, and the ease of visualization of results are pros. For the quantum wave packet dynamics, the complexity of setting up an appropriate model Hamiltonian, use of approximate fitted potentials, and the... 

After the introduction of frequency resolved CARS by Maker and Terhune [1], time resolved experiments became possible with the invention of high power lasers with femtosecond resolution. Leonhardt [2] and for example Hayden [3] performed femtosecond CARS experiments in liquids. A first femtosecond time resolved CARS experiment in gas phase was performed by Motzkus et. al. [4] where the wave packet dynamics of the dissociation of Nal was monitored. The first observation of wave packet dynamics in gaseous iodine was reported by Schmitt et al. [5]. They were able to observe dynamics in both, the ground and excited state with the same experiment. A summary of high resolution spectroscopy in gas phase by nonlinear methods is given by Lang et al. [6]. 

S.K. Gray, Wave packet dynamics of resonance decay An iterative equation approach with application to HCO- -H+CO, J. Chem. Phys. 96 (1992) 6543. 

Y. Tanimura and S. Mukamel. Multistate quantum Fokker-Planck approach to nonadiabatic wave packet dynamics in pump-probe spectroscopy. J. Chem. Phys., 101 3049, 1994. 

Coalson, R.D. and Karplus, M. (1982). Extended wave packet dynamics exact solution for collinear atom, diatomic molecule scattering, Chem. Phys. Lett. 90, 301-305. 

Feit, M.D. and Fleck, J.A., Jr. (1984). Wave packet dynamics and chaos in the Henon-Heiles system, J. Chem. Phys. 80, 2578-2584. 

Gray, S.K. and Wozny, C.E. (1989). Wave packet dynamics of van der Waals molecules Fragmentation of NeCl2 with three degrees of freedom, J. Chem. Phys. 91, 7671-7684. 

Henriksen, N.E. and Heller, E.J. (1988). Gaussian wave packet dynamics and scattering in the interaction picture, Chem. Phys. Lett. 148, 567-571. 

Manthe U. and Koppel, H. (1990a). New method for calculating wave packet dynamics Strongly coupled surfaces and the adiabatic basis, J. Chem. Phys. 93, 345-356. 

Manthe, U. and Koppel, H. (1991). Three-dimensional wave-packet dynamics on vibron-ically coupled dissociative potential energy surfaces, Chem. Phys. Lett. 178, 36-42. 

Manthe, U., Koppel, H., and Cederbaum, L.S. (1991). Dissociation and predissociation on coupled electronic potential energy surfaces A three-dimensional wave packet dynamical study, J. Chem. Phys. 95, 1709-1720. 

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