Understanding the effect of dynamical barrier on bond breaking process:
For molecules like H2O,D2O and CH2 large volumes of classical vibrational phase spaces are found to be non-dissociating even well above the dissociation energy of a single bond. Classical dynamical study suggests the existence of dynamical constant of motion, which will have the effect of creating classical dynamical barrier, preventing the dissociation and hence showing the non RRKM behavior. The standard approach to build effective spectroscopic Hamiltonian is well understood for systems below the dissociation energy of a single bond. But here we need to incorporate the effect of continuum into the effective spectroscopic Hamiltonian , which is one of the key challenges in this area.