Molecular-dynamics (MD) simulations have been performed for the growth of a spherical methane-hydrate nano-crystallite, surrounded by a supersaturated water-methane liquid phase, using both a hybrid and global-system thermostatting approach. It was found that hybrid thermostatting led to more sluggish growth and the establishment of a radial temperature profile about the spherical hydrate crystallite, in which the growing crystal phase is at a higher temperature than the surrounding liquid phase in the interfacial region, owing to latent-heat dissipation. In addition, Onsager's-hypothesis fluctuation-dissipation analysis of fluctuations in the number of crystal-state water molecules at the interface shows slower growth. (C) 2019 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.