A Simple Approach to the Vapor Pressure of Bulk and Nano Systems

MATIAS H. FACTOROVICH; VALERIA MOLINERO; DAMIAN A. SCHERLIS

Congreso; American Conference on Theoretical Chemistry; 2014

We introduce a simple "Grand Canonical Screening" (GCS) method to accurately compute vapor pressures from molecular dynamics or Monte Carlo simulations. This procedure entails a screening of chemical potentials using a conventional grand canonical scheme, and therefore it is straightforward to implement for any kind of interface making the method not limited to bulk systems. We validate our method for Argon against experimental and Gibbs ensemble data. We also get a good Clapeyron-Clausius relation for the mW water model from which we calculate the DHvap. Finally we study the vapor pressure of water nanodroplets and we find that classical thermodynamics description given by the Kelvin equation and Tolman correction are valid for droplets as small as 1nm.