Excess-entropy scaling of dynamics for methane in various nanoporous materials

Molecular simulation was conducted to test the validity of two excess entropy scaling laws proposed by Rosenfeld and Dzugutov for extending their use in describing the diffusion of CH4 molecules through zeolites and metal–organic frameworks. The functional relationships between self-diffusivity and excess entropy formulated by the two laws are found to hold with the modified pre-exponential scaling parameters. Based on this finding, new relations for the two scaling laws are proposed for predicting the diffusivities of CH4 molecules in nanoporous materials within a wide range of concentrations and temperature conditions.