Explorations of gas hydrate crystal growth by molecular simulations

►A dynamic criterion allows the identification of solid and liquid-like molecules without the limitation of structural order parameters. ►By using a self-adaptive approach and an interface detecting method based on an integration procedure, a system can be maintained roughly at steady state during a crystal growth simulation. ►The growths of both CH4 and H2S hydrates predict unusual polycrystalline structures. ►The heterogeneous crystal growth simulation may provide insights into microscopic mechanisms for annealing of defect structures.