Multiple-time scale accelerated molecular dynamics: Addressing the small-barrier problem

A method for accelerated molecular-dynamics simulation in systems with rare event dynamics that span a wide range of time scales was presented. On the fly, groups of recurrent states connected by small energy barriers was detected using a variant of hyperdynamics. The proposed method was applied to stimulate cluster diffusion and the initial growth of CO on CU(001). It was observed that the proposed method correctly follows the slow events, which enables the stimulation of much larger times than with accelerated molecular dynamics alone.