|Budget Amount *help
¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 2001 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 2000 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1998 : ¥1,000,000 (Direct Cost : ¥1,000,000)
1. Hierarchical Structure of Molecular Dynamics
(1) We proposed a novel technique called "derivative state analysis", which enables us to grasp a hierarchical structure in the sequential intramolecular vibrational energy re-distribution (IVR), and applied it to acetylene molecule. Wave function of feature state in vibrationally highly excited state of water was calculated for the first time. We proposed an experimental method, in which a hierarchical structure of IVR can be detected based on the technique of fs-laser chemistry.
(2) We presented a basic theory to rationalize the existence of irreversible relaxation on the basis of quantum mechanics, This theory clarifies the connection between the relaxation rate and structure of molecular energy levels.
2. We clarified the origin of randomness observed in molecular collisions. Semiclassical theory shows that when underlying classical dynamics is chaotic, an infinite number of classical paths contribute to quantum mechanical transition amplitudes. In that case, the transition amplitudes behave as Gaussian random numbers due to the central limit theorem. This randomness can be one possible origin of statistical behavior in chemical reactions.
3. Ionization of diatomic molecules in intense laser fields was investigated. When the laser intensity exceeds a threshold, diatomic molecules exhibit stabilization against ionization. In the present study, the stabilization is ascribable to overlapping resonance. On the other hand, the origin of RRKM behavior, which is widely regarded as a representative case of the statistical behavior, is also shown to be overlapping resonance. Ionization in intense fields and statistical behavior are linked with a profound connection through overlapping resonance, which is a phenomenon typical to strongly-coupled systems.