Water/organic liquid interface properties with amine, carboxyl, thiol, and methyl terminal groups as seen from MD...

Molecular dynamics simulations were performed to study structural and dynamic properties of polar butanamine/water/butanamine, pentanoic acid/water/pentanoic acid, butanethiol/water/butanethiol, and nonpolar pentane/water/pentane systems. The mass density profiles along the interface normal to the organic liquid/water system, the difference in the local structure of H $$ O molecules in bulk and in the vicinity of interface, as well as the diffusion behavior of water molecules at the interface with above-mentioned organic liquids have been investigated. Our MD simulation has shown that the diffusion of water molecules across the water/organic liquid interface is influenced by the hydrogen bonds $$ between water molecules and the terminal groups of organic liquids. It was found that the loss of the hydrogen bonds $$ in the nonpolar organic liquid leads to a decrease in the value of the normal component of the diffusion coefficient $$ , while the tangential diffusion coefficients, both $$ and $$ , increase.