Phase space structure of triatomic molecules
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403 (United States)
The bifurcation structure is investigated for a Hamiltonian for the three coupled nonlinear vibrations of a highly excited triatomic molecule. The starting point is a quantum Hamiltonian used to fit experimental spectra. This Hamiltonian includes 1:1 Darling{endash}Dennison resonance coupling between the stretches, and 2:1 Fermi resonance coupling between the stretches and bend. A classical Hamiltonian is obtained using the Heisenberg correspondence principle. Surfaces of section show a pronounced degree of chaos at high energies, with a mixture of chaotic and regular dynamics. The large-scale bifurcation structure is found semianalytically, without recourse to numerical solution of Hamilton{close_quote}s equations, by taking advantage of the fact that the spectroscopic Hamiltonian has a conserved polyad quantum number, corresponding to an approximate constant of the motion of the molecule. Bifurcation diagrams are analyzed for a number of molecules including H{sub 2}O, D{sub 2}O, NO{sub 2}, ClO{sub 2}, O{sub 3}, and H{sub 2}S. {copyright} {ital 1997 American Institute of Physics.}
- DOE Contract Number:
- FG06-92ER14236
- OSTI ID:
- 530056
- Journal Information:
- Journal of Chemical Physics, Vol. 107, Issue 1; Other Information: PBD: Jul 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Stretch-bend combination polyads in the Ã1Au state of acetylene, C2H2
Infrared laser spectroscopy of the n-propyl and i-propyl radicals: Stretch-bend Fermi coupling in the alkyl CH stretch region