Wavepackets computational applications

Since the classical treatment has its restrictions and the applicability of the quantum OCT is limited to low-dimensional systems due to its formidable computational cost, it would be very desirable to incorporate the semiclassical method of wavepacket propagation like the Herman-Kluk method [20,21] into the OCT. Recently, semiclassical bichromatic coherent control has been demonstrated for a large molecule [22] by directly calculating the percent reactant as a function of laser parameters. This approach, however, is not an optimal control. 

As with the EDA calculations, for reasons of computational feasibility we did not include any scattering states in the basis set, since the field was weak, 8.75x10 W/cm. On the other hand, for peak intensities many orders of magnitude larger than the one used in this application, the effect of the continuum states on the formation of coherent wavepackets and on the various multiphoton processes cannot be ignored. However, in that case, the solution of the TDSE with the full electric operator would be a formidable task both theoretically and computationally. 

Abstract. This paper presents an overview of the time-dependent quantum wavepacket approach to chemical reaction dynamics. After a brief review of some early works, the paper gives an up-to-date account of the recent development of computational methodologies in time-dependent quantum dynamics. The presentation of the paper focuses on the development of accurate or numerically exact time-dependent methods and their specific applications to tetraatomic reactions. After summarizing the current state-of-the-art time-dependent wavepacket approach, a perspective on future (development is provided. 

Neuhauser D, Baer M, Judson RS, Kouri DJ (1991) The application of time-dependent wavepacket methods to reactive scattering. Comput Phys Common 63(13) 460... 

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