Nonlinear dynamics of vibration-rotation interactions: Rigid bender H ₂O

A classical nonlinear dynamics analysis of intramolecular vibration-rotation interaction is presented. The system studied is a water molecule which is allowed to rotate in three dimensions and bend, but angular momentum conservation is used to reduce the problem to two degrees of freedom. A classical perturbation theory treatment is developed which accurately treats first order corrections to the dynamical frequencies and which provides a qualitative picture of the role of nonlinear resonances in the onset of vibration-rotation chaos. Additionally, a classical trajectory study of the high j, high E regime provides information about the onset of chaos. The relationship of this work to an earlier trajectory study and a comparison of the results to those found for coupled oscillator systems are discussed. © 1986 American Institute of Physics.