Molecular dynamics study of the potential of mean force of SDS aggregates

Shinji Kawada, Kazushi Fujimoto, Noriyuki Yoshii, Susumu Okazaki
2017 Journal of Chemical Physics  
We study a three-dimensional system of self-propelled Brownian particles interacting via the Lennard-Jones potential. Using Brownian dynamics simulations in an elongated simulation box, we investigate the steady states of vapour-liquid phase coexistence of active Lennard-Jones particles with planar interfaces. We measure the normal and tangential components of the pressure tensor along the direction perpendicular to the interface and verify mechanical equilibrium of the two coexisting phases.
more » ... oexisting phases. In addition, we determine the non-equilibrium interfacial tension by integrating the difference of the normal and tangential components of the pressure tensor and show that the surface tension as a function of strength of particle attractions is well fitted by simple power laws. Finally, we measure the interfacial stiffness using capillary wave theory and the equipartition theorem and find a simple linear relation between surface tension and interfacial stiffness with a proportionality constant characterized by an effective temperature. Published by AIP Publishing. [http://dx.
doi:10.1063/1.4998549 pmid:28863544 fatcat:e73rr2hfdfeavmfteasqkcdf6a