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We consider the accuracy of several methods for combining forward and reverse free-energy perturbation averages for two systems ͑labeled 0 and 1͒. The practice of direct averaging of these measurements is argued as not reliable. Instead, methods are considered of the form ␤(A 1 ϪA 0) ϭϪln͓͗w(u)exp(Ϫ␤u/2)͘ 0 /͗w(u)exp(ϩ␤u/2)͘ 1 ͔, where A is the free energy,(More)
Free-energy simulation methods are applied toward the calculation of cluster integrals that appear in diagrammatic methods of statistical mechanics. In this approach, Monte Carlo sampling is performed on a number of molecules equal to the order of the integral, and configurations are weighted according to the absolute value of the integrand. An(More)
We use the Mayer sampling method, with both direct and overlap sampling, to calculate and compare classical virial coefficients up to B6 for various water models (SPC, SPC/E, MSPC/E, TIP3P, and TIP4P). The precision of the computed values ranges from 0.1% for B2 to an average of 25% for B6. When expressed in a form scaled by the critical properties, the(More)
Vapor–liquid interfacial tension of square-well ͑SW͒ fluids is calculated using three different methods viz., molecular dynamics ͑MD͒ with collision-based virial evaluation, Monte Carlo with virial computed by volume perturbation, and Binder's density-distribution method in conjunction with grand-canonical transition-matrix Monte Carlo ͑GC-TMMC͒. Three(More)
Prewetting transitions are studied for Lennard-Jones (LJ) based dimer forming associating fluids, on a structureless surface represented by LJ 9-3 type potential, for various association strengths using grand-canonical transition matrix Monte Carlo (GC-TMMC) and histogram reweighting techniques. Occurrences of prewetting transition are observed for(More)
Three-stage pseudo-supercritical transformation path and multiple-histogram reweighting technique are employed for the determination of solid-liquid coexistence of the Lennard-Jones (12-6) fluid, in a structureless cylindrical pore of radius, R, ranging from 4 to 20 molecular diameters. The Gibbs free energy difference is evaluated using thermodynamic(More)
A novel nanocomposite polyvinyl alcohol precursor-based material dispersed with the web of carbon microfibers and carbon nanofibers is developed as lithium (Li)-ion electrolyte battery separator. The primary synthesis steps of the separator material consist of esterification of polyvinyl acetate to produce polyvinyl alcohol gel, ball-milling of the(More)
We present the effect of surface attraction on the vapor-liquid equilibria of square well (SW) fluids in slit pores of varying slit width from quasi 3D to 2D regime using molecular simulation methodologies. Four to five distinct linear regimes are found for shift in the critical temperature with inverse slit width, which is more prominent at higher surface(More)
Vapor-liquid phase equilibria of square-well (SW) fluids of variable interaction range: lambdasigma=1.25, 1.75, 2.0, and 3.0 in hard slit pores are studied by means of grand-canonical transition-matrix Monte Carlo (GC-TMMC) simulation. Critical density under confinement shows an oscillatory behavior as slit width, H, reduced from 12sigma to 1sigma. Two(More)
The adsorption and separation behavior of SO2-CO2, SO2-N2 and CO2-N2 binary mixtures in bundles of aligned double-walled carbon nanotubes is investigated using the grand-canonical Monte Carlo (GCMC) method and ideal adsorbed solution theory. Simulations were performed at 303 K with nanotubes of 3 nm inner diameter and various intertube distances. The(More)