Molecular modelling and simulation of the surface tension of real quadrupolar fluids

Abstract

This is demonstrated using the model for carbon dioxide as an example.

Simultaneous description of bulk and interfacial properties of fluids by the Mie potential

“…Molecular modelling and simulation based on force fields is a promising way of predicting these thermodynamic properties. However, it is a topic of controversial discussion to what extent effective pair potentials are capable of reproducing bulk and interfacial properties of real fluids at the same time [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The present work reports on bulk and interfacial properties of the Mie fluid and adresses the question of the simultaneous description of these properties by that model.…”

“…Carbon dioxide is used as a test case. There are several 2CLJQ models [4,40,[76][77][78] and three site models with superimposed electrostatics [79][80][81][82] for the description of CO 2 and one model based on a single-site four-parameter Mie potential [7].…”

“…The Pareto set for the multicriteria optimization problem described above was determined in different ways depending on the potential: For the LJ and the Mie model, a brute force sampling of the parameter space was performed [4], while the 2CLJQ Pareto set was determined by a combination of sandwiching and hyperboxing, for details see Stöbener et al [6].…”

Models for viscosity, thermal conductivity, and surface tension of selected pure fluids as implemented in REFPROP v10.0

“…Coefficients are given in Tables 2-4. For surface tension, the value of n0 for propyne from Mulero et al (Mulero et al, 2012) was used, and σ0 was adjusted so that the surface tension of propadiene fell in between propylene and propyne as suggested by the simulations of Werth et al (Werth et al, 2015). Coefficients are given in Table 5 for surface tension.…”

Comment on “The gas-liquid surface tension of argon: A reconciliation between experiment and simulation” [J. Chem. Phys. 140, 244710 (2014)]

“…However, an adjustment of the potential parameters may improve the description of the surface tension as discussed by Stöbener et al 14,15 Nonetheless, careful simulations are required to come to definitive conclusions. A more general approach has to be followed that also considers the physically inappropriate repulsive term (∼r −12 ) of the Lennard-Jones potential 16,17 as well as the higher-order dispersion terms (∼r −8 , ∼r −10 ).…”