A Preliminary Study On Reaction Mechanism Of Molecular Ring Turnover Base On The Snap-through Buckling Theory Of Shallow Spherical Shell

It is found that the inversion of molecular ring in the2-picoline pyrolysis mechanism is a process of mechanical catastrophe on the configuration and energy. The inversion mechanical of molecular ring provide the effective method to study the transition state. Due to the complex of the microscopic properties of molecular internal, there is no appropriate method to study the inversion of the ring in the2-picoline pyrolysis mechanism.From microcosmic angle, the molecular ring turnover is an unknown area, but the study on snap-through of macro-structure model is more mature. The shallow spherical shells subject to uniform load have a similar jump changes In this paper, the snap-through of macro-structure was be used to study the inversion mechanical of the molecular ring in analogy method. Firstly, shallow spherical shells under transverse uniform loading was analyzed in nonlinear large deflection method based on the large deflection of shallow spherical shell deformation equations, then the cusp catastrophe model and the critical load expression was established. Secondly, the snap-through buckling behavior of shallow spherical shell, subjected to uniform lateral force, is investigated with the Arc-length method in ANSYS12.0. It is obtain that the curve of force and deflection, which is similar with the curve of the cusp catastrophe model, and the major factors that is the impact on snap-through was explained. The theoretical analysis results and numerical simulation results were compared to verify the rationality about shallow spherical shells under transverse uniform loading. Finally considering the complexity of the molecular structure of2-methylpyridine, mechanical model of the micro-chemical bond was be simplified and were compared with the snap-through model of shallow spherical shell, initially concluded that the factors which impact on2-methylpyridine ring snap or not is the position of the atom outside the molecular ring.And applied catastrophe theory, it is consider that atoms outside the molecular ring are control variables,0(∠C6-C1-C4) is the state variables, with relative position of the atom outside the molecular ring change, the state variables0(∠C6-C1-C4) will be snap-through in a special angle...