Chaotic motion in bending induced intramolecular transition: A case study of HCN, HNC and the transition state

Chaotic motion in the bending induced intramolecular transition of HCN, HNC and the transition state is explored by three approaches: (1) Lyapunov analysis, which is based on the classical phase space for the levels, (2) statistical analysis of the distribution of the adjacent level spacing and (3) analysis based on level spacing dips, which integrates the concepts of pendulum dynamics and quantized levels. The three analyses show consistent conclusions: chaos appears only above the transition point and the degree of chaos shows fluctuations as the level energy increases.