查看文章

We use bias-exchange metadynamics simulations to quantify the adsorption of anti-agglomerant molecules to the surface of the sII methane–propane gas hydrate. Multiple steps of sampling binding configurations, measuring their free energies, and finding their equilibrium distribution are combined into a single-step modeling using bias-exchange metadynamics. We showed that the current method quantitatively and qualitatively reproduces the previously measured binding free energies for the adsorption of the quaternary ammonium salt to the hydrate surface. Finally, we used the developed approach together with a rational chemical design to engineer the tail of the AA molecule. We used the quaternary ammonium salt, which has been proven to be effective AA in experimental conditions as the initial configuration. This AA has a long flexible tail, which causes a sizeable entropic penalty upon binding, which …