Structural feature in dynamical processes accelerated transition state calculations

Minimum energy path (MEP) search is a vital but often very time-consuming method to predict the transition states of versatile dynamic processes in chemistry, physics, and materials science. In this study, we reveal that the largely displaced atoms in the MEP structures maintain transient chemical bond lengths resembling those of the same type in the stable initial and final states. Based on this discovery, we propose an adaptive semirigid body approximation (ASBA) to construct a physically reasonable initial guess for the MEP structures, which can be further optimized by the nudged elastic band method. Examination of several distinct dynamical processes in bulk, on crystal surface, and through two-dimensional system shows that our transition state calculations based on the ASBA results are robust and significantly faster than those based on the popular linear interpolation and image-dependent pair potential methods.