Surface tension of water and acid gases from Monte Carlo simulations

Abstract

We report direct Monte Carlo (MC) simulations on the liquid-vapor interfaces of pure water, carbon dioxide, and hydrogen sulfide. In the case of water, the recent TIP4P/2005 potential model used with the MC method is shown to reproduce the experimental surface tension and to accurately describe the coexistence curves. The agreement with experiments is also excellent for CO(2) and H(2)S with standard nonpolarizable models. The surface tensions are calculated by using the mechanical and the thermodynamic definitions via profiles along the direction normal to the surface. We also discuss the different contributions to the surface tension due to the repulsion-dispersion and electrostatic interactions. The different profiles of these contributions are proposed in the case of water.

Interfacial properties of selected binary mixtures containing n-alkanes

“…19, the equilibrated system (state 0) with interfacial area According to our results, we found that γ is constant in the range 10 -5 < ξ < 10 -3 . The value of ξ used in this work is 5 × 10 -4 , which is commensurate with previous other similar application of the TA method [68,[71][72][73][74][75] . All the TA calculations are performed by post-processing an uninterrupted MD run, as the perturbations have no effect on the dynamics of the system.…”

“…This method, referred to as the test area (TA) method (see Gloor et al [68] Errington and Kofke [69] and Ghoufi et al [70] for a review of this approach) is used herein.…”

Calculation of the long-range interactions for interfacial properties

“…The computational procedures of the molecular simulation of the liquid-vapour interface can be found in previous papers [12,13,14,15,16,17]. The force-field used in the molecular modelling of the grafted system and the description of the computational procedures can be also found elsewhere [11].…”

On the molecular origin of high-pressure effects in nanoconfinement: The role of surface chemistry and roughness

“…We refer to this as the volume perturbation method (sometimes referred to as the ghost volume change method) [23][24][25][26][27][28][29] of pressure calculation. For a homogeneous phase the pressure can be obtained by [23][24][25][26][27][29][30][31][32] …”