Molecular Dynamics of Wetting

The use of molecular dynamic modeling of wetting was first described in a crucial 1976 work by Yushenko and Shchukin [25,26], also presented at the plenary lecture of the Seventh International Symposium on Surfactants (Moscow, USSR, 1976), where the presentation was accompanied by a short film illustrating the findings. 

While a thermodynamic description of interfacial phenomena provides means for their macroscopic description, the use of molecular dynamic simulation enables one to study these phenomena on a molecular level. One of the first and most interesting developments in this direction was the analysis of the behavior of a drop of liquid on wetting and nonwetting solid surfaces. As a result, it was possible to reveal molecular insights into the mechanisms of wetting and nonwetting on a qualitative level and to relate these findings to the thermodynamic characteristics of these systems. 

In molecular dynamic simulation, a 2D system giving a pictorial illustration of the arrangement of molecules at various time intervals was produced by computer. A solid substrate was modeled by a box, the bottom of which contained a layer of molecules fixed on a substrate. The attraction of the mobile molecules to the fixed ones corresponded to the interaction of a substrate with a semiinfinite 2D crystal built out of molecules belonging to the main component of a fluid. The other walls of the box were the reflecting walls. The liquid was represented by 19 mobile molecules, which was sufficient for observing the studied phenomena. The interaction between the molecules was described by the Lennard-Jones 6-12 potential. The parameters of the interaction potential of 

Physical-Chemical Mechanics of Disperse Systems and Materials 

The results presented earlier have clearly indicated that a molecular dynamic simulation enables one to observe all of the basic physical-chemical phenomena in the processes of wetting and spreading and enables one to conduct a rigorous analysis of the molecular mechanisms of various interactions taking place at the interfaces. The method of molecular dynamics offers a unique opportunity to study the mechanisms of the interfacial phenomena at a microscopic level. The equilibrium state of interfacial phenomena can be investigated using statistical methods, such as a Monte Carlo simulation [29]. 

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