Particle-Resolved Phase Identification in Two-Dimensional Condensable Systems

A method for phase identification (MPI) in two-dimensional (2D) condensable systems is proposed on the basis of the analysis of the Voronoi cells’ characteristics. A simple algorithm is developed for determination of particles belonging to a condensate, a gaseous state, and an interface between them (“surface”). The efficiency and stability of the developed method is studied using molecular dynamics simulations and calculation of binodals in 2D systems with both short- and long-range attraction between particles. To illustrate prospectives of the method for experimental studies, 2D clusters of 2.12 μm diameter colloidal silica particles assembled in a rotating external electric field have been analyzed using the MPI. The results prove that the MPI possesses high accuracy and can be applied to analyze in detail both simulation data (obtained by molecular dynamics or Monte Carlo methods) and results of particle-resolved experimental studies (with colloidal suspensions and complex (dusty) plasmas) of solids ...