Summary of Research Interests

The research of our group exploits the symmetry of molecules and of their interactions in order to understand the basic laws that govern molecular behavior. This symmetry is used to explain molecular properties, chemical reactions, and molecular energy transfer. The symmetry of importance includes not only that of the electronic orbital motion in a structured molecule (the molecular point group symmetry applied to, for example, ligand field theory), but also the electron spin motion arising from relativistic considerations, especially from the motion of half integral spin angular momentum (for example, double point-group symmetry applied to free radicals and to spin-forbidden processes). Besides the symmetry of electronic motion, that associated with other motions is also considered: vibrational, rotational and translational motions, their interconversion in the presence or absence of external fields, and their compatiblilty in the presence of nuclear spin permutations (continuous group symmetry applied to angular momentum and polarization correlation in molecular collision, dissociation and photo-fragmentation). Besides bound molecules of clear structure, symmetry considerations are also important in structureless non-rigid "molecules" and their transformations (for example, permutation group symmetry applied to clusters and surface reactions). Besides static interactions and implied forward flow of time, symmetry is also considered in the backward flow of time, for example, in the treatment of degenerate states and time symmetric interactions (for example, time-reversal symmetry applied to optical rotation and multiphoton transitions). Symmetry and mechanisms for isomeric transformation and addition/elimination reactions of fullerene clusters are being studied with exact and clear two-dimensional structural diagrams. Cyclic symmetry of two-electron geminals with Jahn-Teller vibronic interactions are used to investigate high Tc superconductivity theory.

Selected publications

"Vibrationally Resolved Inelastic Scattering and Charge Transfer in Hs - C2H4 Collisons." Aristov, N.; Maring, W.; Niedner-Schattleburg, G.; Toennis, J. P.; Chiu, Y. -N.; K?ppel, H. J. Chem. Phys. 1993, 99, 2682.

"Symmetry and Geometry Structure of Polyhedral Atomic and Molecular Clusters." Chiu, Y. - N.; Wang, B. C. J. Mol. Struct. (Theochem) 1993, 283, 13.

"Spin Rovibronic Symmetry in the Formation of Van Der Waals Complexes." Chiu, Y. - N. Struct. Chem. 1991, 2, 635.

"Spin Symmetry and Interaction Mechanisms in Free Radical Reactions." Chiu, Y. - N.; Gong, M. Chem. Phys. 1990, 145, 397.

"Angular Distributions, Rotational Summations, and Integrations in the Quadrupole and Two-photon Photodissociation of Molecules." Lai, S. T.; Chiu, Y. - N. J. Mathematical Physics 1990, 31, 1261.