Density functional theory based calculations have been performed to study hydrogen bond formation between pentagonal dodecahedron methane hydrate cage and chitosan. The role of chitosan as a potential methane hydrate inhibitor is elucidated, based on electronic structure property correlations. Geometry optimization, frontier orbitals and natural bond orbital (NBO) analysis of methane hydrate pentagonal dodecahedron cage with and without the presence of chitosan molecule using B3LYP DFT-D/6-31++G(d,p) have been performed. Calculated interaction energies, geometrical parameters and NBO analysis reveal that chitosan has strong potential to hinder the formation of pentagonal dodecahedron methane hydrate cage.
Chitosan, Natural bond orbital, Methane hydrate inhibitor, Frontier orbital