Thin-thick surface phase coexistence and boundary tension of the square-well fluid on a weak attractive surface.
Prewetting transition is studied for the square-well fluid of attractive-well diameter lambda(ff)sigma(ff)=1.5 in the presence of a homogeneous surface modeled by the square-well potential of attractive well from 0.8sigma(ff) to 1.8sigma(ff). We investigate surface phase coexistence of thin-thick film transition using grand-canonical transition matrix Monte Carlo (GC-TMMC) and histogram reweighting techniques. Molecular dynamics (MD) and GC-TMMC are utilized to predict the properties of the fluid for various surface fluid affinities. Occurrences of prewetting transition with the variation of surface affinity are observed for a domain of reduced temperature from T(*)=0.62 to 0.75. We have used MD and GC-TMMC+finite size scaling (FSS) simulations to calculate the boundary tension as a function of temperature as well as surface affinity. Boundary tensions via MD and GC-TMMC+FSS methods are in good agreement. The boundary tension increases with the decrease of wall-fluid affinity. Prewetting critical properties are calculated using rectilinear diameter approach and scaling analysis. We found that critical temperature and density increase with the decrease of wall-fluid affinity.
Singh
Jayant K
JK
Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, India. jayantks@iitk.ac.in
Sarma
Gautam
G
Kwak
Sang K
SK
D000465:Algorithms; D003198:Computer Simulation; D008956:Models, Chemical; D009010:Monte Carlo Method; D044367:Phase Transition; D012997:Solvents / Q000737:chemistry*; D013500:Surface Tension; D013696:Temperature
D012997:Solvents