Action localization and resonance of highly excited vibrational triatomic system

An algebraic Hamiltonian for H2O, D2O, H2S, CH2 of CH2Br2 and CD2 of CD2Br2 containing anharmonicities and resonances is proposed with coefficients el ucidated from the fit with the experimentally observed levels. It is demons trated that most often the anharmonic parts show clues of action (energy) l ocalization. Resonances are shown full of periodic, quasiperiodic and chaot ic motion, while the intersection of the various resonances is full of chao tic motion. The barrier in intramolecular vibrational relaxation with extre me mutual irrational ratios of resonance frequencies is shown full of perio dic or quasiperiodic motion, leading to the dynamical bottlenecks. (C) 2000 Published by Elsevier Science B.V. All rights reserved.