Molecular Insights into the Heterogeneous Crystal Growth of sI Methane Hydrate

In this paper we report a successful molecular simulation study exploring the heterogeneous crystal growth
of sI methane hydrate along its [001] crystallographic face. The molecular modeling of the crystal growth of
methane hydrate has proven in the past to be very challenging, and a reasonable framework to overcome the
difficulties related to the simulation of such systems is presented. Both the microscopic mechanisms of
heterogeneous crystal growth as well as interfacial properties of methane hydrate are probed. In the presence
of the appropriate crystal template, a strong tendency for water molecules to organize into cages around
methane at the growing interface is observed; the interface also demonstrates a strong affinity for methane
molecules. The maximum growth rate measured for a hydrate crystal is about 4 times higher than the value
previously determined for ice I in a similar framework (Gulam Razul, M. S.; Hendry, J. G.; Kusalik, P. G.
J. Chem. Phys. 2005, 123, 204722).