Nonadiabatic chemical dynamics control

NONADIABATIC CHEMICAL DYNAMICS COMPREHENSION AND CONTROL OF DYNAMICS, AND MANIFESTATION OF MOLECULAR FUNCTIONS... 

Nonadiabatic Chemical Dynamics Comprehension and Control OF Dynamics, and Manifestation of Molecular Functions By Hiroki Nakamura... 

Our basic strategy for controlling chemical dynamics is based on the idea that there are two basic elements of wavepacket motion in chemical dynamics (i) electronic nonadiabatic transitions between adiabatic potential energy surfaces and (ii) wavepacket motion on a single adiabatic potential energy surface. If we could control these two basic motions of wavepackets, it would become possible to control various kinds of realistic chemical dynamics. 

In Chapter 5, we have studied some of the effects of laser fields on chemical dynamics. In particular, we have investigated how time-resolved photoelectron spectroscopy can be used as a very good means to monitor the femtosecond-scale nuclear dynamics such as the passage across nonadia-batic regions. The modulation of nonadiabatic interactions (both avoided crossing and conical intersection) is also among the main subjects from the view point of control of chemical reaction. Chapter 7, on the other hand, has treated nonadiabatic electron wavepacket dynamics relevant to chemical reactions. Here in this chapter, we therefore rise to the theory of electron dynamics in laser fields mainly associated with chemical dynamics. 

Since chemical reactions usually show significant nonadiabaticity, there are naturally quantitative errors in the predictions of the vibrationally adiabatic model. Furthermore, there are ambiguities about how to apply the theory such as the optimal choice of coordinate system. Nevertheless, this simple picture seems to capture the essence of the resonance trapping mechanism for many systems. We also point out that the recent work of Truhlar and co-workers24,34 has demonstrated that the reaction dynamics is largely controlled by the quantized bottleneck states at the barrier maxima in a much more quantitative manner than expected. 

Chapter 7 continues the presentation of nonadiabatic electron wavepacket d mamics as applied in various chemical reactions, mainly in electronically excited states. Quantization the branching paths (non-Born-Oppenheimer paths) will be also discussed. Likewise, in Chap. 8, the electron wavepacket dynamics is considered for molecules placed in laser fields. In addition to the ordinary nonadiabatic transitions due to the Born-Oppenheimer approximation, novel nonadiabatic transitions due to optical interactions appear to need special cares. This chapter is to be continued to future studies of laser design of electronic states and concomitant control of chemical reactions. 

Eckert-Maksic, M., Vazdar, M., Ruckenbauer, M., Barbatti, M., Muller, X, 8c Lischka, H. (2010b). Matrix-controlled photofragmentation of formamide Dynamics simulation in argon by nonadiabatic QM/MM method. Physical Chemistry Chemical Physics, 12(39), 12719-12726. 

Abstract We present a general theoretical approach for the simulation and control of ultrafast processes in complex molecular systems. It is based on the combination of quantum chemical nonadiabatic dynamics on the fly with the Wigner distribution approach for simulation and control of laser-induced ultrafast processes. Specifically, we have developed a procedure for the nonadiabatic dynamics in the framework of time-dependent density functional theory using localized basis sets, which is applicable to a large class of molecules and clusters. This has been combined with our general approach for the simulation of time-resolved photoelectron spectra that represents a powerful tool to identify the mechanism of nonadiabatic processes, which has been illustrated on the example of ultrafast photodynamics of furan. Furthermore, we present our field-induced surface hopping (FISH) method which allows to include laser fields directly into the nonadiabatic... 

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