Dynamic and equilibrate MD measurements of disjoining pressure according to its original definition.

The concept of disjoining pressure has drawn attention since its first appearance in colloidal chemistry in the 1930s. Almost every scenario with liquid nano and sub-nano film is considered to be related to or even dominated by disjoining pressure. However, debates also last for years. Recently, researchers have explored the physical essence behind it computationally, while few computational works reproduced the discontinuity i.e. the pressure jump in experiments. In this study, a dynamic simulation with a large reservoir according to the very original definition of disjoining pressure by B. V. Derjaguin based on the experiment is conducted and the pressure jump is observed. The disjoining pressure isotherm is found to vary in four dynamic stages, and the liquid re-ordering stage corresponds to the disjoining pressure jumps. The understanding of disjoining pressure based on liquid molecular packing structure could pave the way to a predictive modeling of disjoining pressure. [ABSTRACT FROM AUTHOR]