Joint Research on Quantum Control of Reaction Dynamics

本研究项目的主要目的是发展化学反应动力学的量子控制理论。为此，我们集中讨论了三个主题：1)偏振激光对核波包的控制；2)分子取向的量子控制；3)核波包运动和电子波包运动的精确解。这些课题的研究成果总结如下：1.利用偏振激光脉冲控制核波包我们考虑了光子偏振效应，发展了多维体系反应的量子控制理论。将这一理论应用于双线偏振激光脉冲诱导的氰化氢异构化反应，证明了这种偏振激光脉冲能有效地提高异构化速率。这种双极化脉冲也被用来控制有趣的化学反应，例如从外消旋体中选择性地制备对映体。量子控制…更多的分子取向为了控制气相反应，分子在气相中的取向是非常重要的。我们发展了一种基于偶极跃迁和非共振拉曼散射干涉的分子取向理论。变量为双光子场的频率ω和2ω、其相位差和光子场的幅度。通过从头算偶极矩和极化率函数，将该理论应用于HCN。考虑了旋转的影响。原子核和电子波包运动的精确解为了描述分子在强脉冲激光作用下的超短动力学，必须把电子和原子核都当作波包来处理。我们成功地用波包精确地求解了简单双原子分子的含时薛定谔方程。这是基于双重变换，以避免在临界点的能量发散。较少

The main purpose of this research project was to develop a theory for quantum control of chemical reaction dynamics. For this purpose, we have concentrated ourselves to three subjects : 1) control of nuclear wave packets by polarized laser lights, 2) quantum control of molecular orientation and 3) exact solutions of both nuclear and electronic wave packet motion. The results of these subjects are summarized as follows.1. Control of nuclear wave packets by polarized laser pulsesWe have developed a quantum control theory of reactions of multidimensional system by take into account effects of photon-polarization. This theory has been applied to isomerization of hydrogen cyanide induced by two linearly polarized laser pulses and has proved that such polarized laser pulses are effectively promote rates of the isomerization. Such double polarized pulses are also used to control chemically interesting reactions, such as selective preparation of enantiomers from racemic body.2. Quantum control … More of molecular orientationIt is very important to orient molecules in gas phase in order to control gas-phase reactions. We have developed a theory of molecular orientation, which is based on interferences between dipole transitions and non resonant Raman scattering. The variables are frequencies ω and 2ω of two-photon fields, its phase differences and amplitudes of the photon fields. This theory has been applied to HCN by performing abinitio MO calculation of dipole moment and polarizability functions. Effects of rotations are taken into account.3. Exact solutions of both nuclear and electronic wave packet motionIn order to describe ultra short dynamics of molecules under intense pulse laser, which brings about Coulomb explosions, it is essential to treat both electrons and nuclei as wave packets. We have succeeded in exactly solving time-dependent Schroedinger equation of a simple diatomic molecules in terms of wave packets. This is base on a dual transformation to avoid divergence of energy at critical points. Less