Classical molecular dynamics of clathrate-methane-water-kinetic inhibitor composite systems
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Classical molecular dynamics simulations of clathrate-methane-water and an inhibitor of clathrate formation are performed using different inhibitor/water ratios and a hydrate system modeled as a 5 126 2 cavity. Vinylpyrrolidone, vinylvalerolactam, L-proline, 1-formylpyrrolidine, and dimethylaminoethyl methacrylate are used as models of clathrate formation kinetic inhibitors. The goal is to get new insights into the behavior of these composite systems in the early stages of clathrate formation, where the inhibitor is thought to perform its main inhibition effect. Before performing the simulations for the clathrate systems, evidence was searched to find if the chosen combination of force fields reproduced the cage effect for an infinitely diluted methane-water system, and the distribution of water and methane surrounding clathrate-like structures. The systems are analyzed via visualization of the trajectories and examination of the radial distribution functions and the mean-square displacements. The inhibitors can be grouped into hydrophilic and hydrophobic types, and their behavior toward water is analyzed on the basis of their structure and intermolecular interactions. It is found that at the initial stages of clathrate formation the hydrophobic inhibitors may act by blocking the surface of the nascent crystals, whereas the hydrophilic ones act mainly by disruption of the water structure. 2007 American Chemical Society.
