Influence of Lennard-Jones Parameters in the Temperature Dependence of Real Gases Diffusion through Nanochannels

Umbrella Sampling Molecular Dynamics has been used to determine transition energies for different guest molecules through hydroquinone beta-clathrate nanochannels, as well as their temperature trend. This clathrate has been shown to successfully enclathrate different types of small gases with remarkable selectivity, and thus it has been proposed as a potential gas separation and storage medium. Most of these potential guest gases can be successfully modeled as single Lennard-Jones spheres. Then, to obtain a general view of diffusion probabilities for different potential guest molecules, a comparative study for different virtual guest molecules described by different Lennard-Jones parameters has been performed. A regular temperature trend has been obtained for the transition energies for the molecular model characteristic parameter range explored. Finally, to locate the transition energy values of real gases within the space of phases explored, calculations have been repeated for molecular models of different noble gases and H-2. The correlation results presented allow a wide interpolation ability for determining the transition energies of potential guest molecules stored or diffusing through the nanochannels of the studied clathrate structure.

Automated summary

Umbrella Sampling Molecular Dynamics method was used to study the transition energies and temperature trend of different guest molecules in hydroquinone beta-clathrate nanochannels. The clathrate can selectively encapsulate various types of small gases, making it a potential candidate for gas separation and storage. Most guest gases can be accurately modeled as single Lennard-Jones spheres.