1.Coherent Control in 3D with multi-electron states
        The reactive molecular collisions is now one of the central activity of chemical reaction dynamics. This reaction can be thought as the key part of chemistry, and the coherent control over it will be more exciting.

        In 1975, Schatz and Kuppermann and Elkowitz and Wyatt simultaneously published the first accurate quantum reactive scattering cross section for H+H2------> H2+H system. In 1980's Sharipo and Krause[4][7] have made excellent jobs on collinear models. Other scholars have also done great jobs on reduced-dimensionality models.

        However, the present work focus on the full three-dimensional (3D) physical space, which is in slow progress. The main difficulty lies in properly treating three bodies or particles which can be free of one another. Serious mathematical problems in such cases are how to solve for a double continuum for three free bodies. Pack and Parker etc. have done exciting progress in 3D problem, using hyperspherical coordinates to rigorously reduce
the double continuum problem to a single continuum.

       In this study we present a way to coherently control a three-atom system in 3 physical dimension, with the possibility of using several electronic wave functions. We choose approach for two reasons:
                                                                                                                                                  Nonadiabatic processes
      Usually the electronic wave function is treated using one specific Born-Oppenheimer(BO) state, where the adiabatic process can be applied. If the initial,intermediate or final system is the mixture of several states, then the system is nonadiabatic, the Born-Oppenheimer approximation is not adequate.
                                                                                                                                                  Conical intersections

      At specific geometries the electronic states will cross each other, which is called the conical intersection. At specific geometries for the triatom system, there are additional symmetry elements and electronic states can physically cross since they belong to different irreducible representations (have different symmetry). When the triatomic system bends the symmetry group is reduced and there is an avoided crossing which results in the usual picture of the conical intersection. Though the conical intersection is slightly above the threshold for three-body break up, both surfaces have regions that are below zero. This means that the conical intersection for the system will be important for all total scattering energies E slightly below the threshold. For energies E slightly above the threshold, multiple electronic states must be used, for the upper state will have the possibility of going to the lower state.

         This bimolecular coherent control scheme can be broken into three parts:

Pumping stage          The three body  photo-assisted recombination , which can be expressed as:                                                                             
                                                                                        A+BC+hv<==========>(ABC)*
where the (ABC)* is the coherent superposition of vibrational-rotation state.
Evolution stage         The time evolution of the superposition state (ABC)*
Dumping stage         Photodissociation, which can be expressed as:
                                                             (ABC)*=====>
A+BC+hv'
AC+B+hv'
AB+C+hv'



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