Computing Anisotropic Cavity Potential for Clathrate Hydrates.

Abstract

Either concerning to the energy production from natural gas hydrates or employing the hydrate technology to gas handling and seawater desalination purposes, various pure and mixture clathrate hydrates need to be understood in terms of their phase behavior and stability. The ab initio methods have compelling implications in quantifying the anisotropic guest-water interactions that are responsible for the guest-specific nature of the hydrates. Howbeit, the accurate cavity interactions for large guests are obscure due to computational infeasibility. With this research gap, we devise the Møller-Plesset theory with Dunning's basis sets that are suitably advanced to the complete basis limit using the Pauling point counterpoise weight. The viability of the proposed scheme is attested with the Raman spectroscopy, second virial coefficient, and viscosity data of methane and its binary hydrates with tetrahydrofuran and cyclopentane. These two promoters are chosen because they are perhaps the most useful and efficient compounds in their class, for which the experimental cage occupancy data with methane are available to validate our new scheme of estimating the hydrate cavity potential.