摘要：

Computer simulations are used to compare and contrast the dynamical behavior of structure I clathrate hydrates with that of ice Ic (cubic lattices). The calculations are based on recently proposed pairwise additive intermolecular potentials for the water molecules. The phonon densities of states of ice Ic and the hydrates are found to be broadly similar, not withstanding their different crystal structures. This fact explains the similarity of the observed heat capacity and infrared data. In the case of the methane hydrate the simulation predicts a distinct dynamical (localized-mode) behavior for methane molecules trapped in each type of cage. 10 figures, 4 tables.

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