Molecular simulation studies were made of diffusion processes in CO2 clathrate hydrates and ice using classical potential models for carbon dioxide and water. The diffusivity was computed using molecular dynamics and Monte Carlo simulations. The diffusion coefficient of CO2 and H2O molecules in clathrate hydrates was found to be 1 x 10-12 and 1 x 10-23m2/s at 273K and 200K, respectively, and the diffusivity of H2O in ice was 1.3 x 10-18m2/s at 200K.

Computations of Diffusivities in Ice and CO2 Clathrate Hydrates via Molecular Dynamics and Monte Carlo Simulations. A.Demurov, R.Radhakrishnan, B.L.Trout: Journal of Chemical Physics, 2002, 116[2], 702-9