Grand canonical Monte Carlo simulation of a model colloid-polymer mixture:Coexistence line,critical behavior,and interfacial tension

摘要

Grand canonical Monte Carlo simulations are used to study phase separation in a simple colloid-polymer model,the so-called Asakura-Oosawa model.To overcome the problem of small acceptance rates of the grand-canonical moves,cluster moves are introduced.Successive umbrella sampling,recently introduced by Virnau and Muller [J.Chem.Phys.120,10925 (2004)],is used to access the phase-separated regime.The unmixing binodal and the interfacial tension are measured and compared to theoretical predictions.By means of finite-size scaling,the behavior close to the critical point is also investigated.Close to criticality,we observe substantial deviations from mean-field behavior.