RT Journal Article
T1 Liquid-liquid interfacial properties of a symmetrical Lennard-Jones binary mixture
A1 Martínez Ruiz, Francisco José, Físico
A1 Moreno-Ventas Bravo, Ignacio
A1 Jiménez Blas, Felipe
AB We determine the interfacial properties of a symmetrical binary mixture of equal-sized sphericalLennard-Jones molecules, σ11 = σ22, with the same dispersive energy between like species, ϵ11 = ϵ22,but different dispersive energies between unlike species low enough to induce phase separation.We use the extensions of the improved version of the inhomogeneous long-range corrections ofJane˘cek [J. Phys. Chem. B 110, 6264 (2006)], presented recently by MacDowell and Blas [J. Chem.Phys. 131, 074705 (2009)] and Martínez-Ruiz et al. [J. Chem. Phys. 141, 184701 (2014)], to dealwith the interaction energy and microscopic components of the pressure tensor. We perform MonteCarlo simulations in the canonical ensemble to obtain the interfacial properties of the symmetricalmixture with different cut-off distances rc and in combination with the inhomogeneous long-rangecorrections. The pressure tensor is obtained using the mechanical (virial) and thermodynamic route.The liquid-liquid interfacial tension is also evaluated using three different procedures, the Irving-Kirkwood method, the difference between the macroscopic components of the pressure tensor, andthe test-area methodology. This allows to check the validity of the recent extensions presented todeal with the contributions due to long-range corrections for intermolecular energy and pressuretensor in the case of binary mixtures that exhibit liquid-liquid immiscibility. In addition to thepressure tensor and the surface tension, we also obtain density profiles and coexistence densitiesand compositions as functions of pressure, at a given temperature. According to our results, the maineffect of increasing the cut-off distance rc is to sharpen the liquid-liquid interface and to increasethe width of the biphasic coexistence region. Particularly interesting is the presence of a relativeminimum in the total density profiles of the symmetrical mixture. This minimum is related witha desorption of the molecules at the interface, a direct consequence of a combination of the weakdispersive interactions between unlike species of the symmetrical binary mixture, and the presenceof an interfacial region separating the two immiscible liquid phases in coexistence
PB American Institute of Physics
SN 0021-9606
SN 1089-7690
YR 2015
FD 2015
LK http://hdl.handle.net/10272/11148
UL http://hdl.handle.net/10272/11148
LA eng
NO Martínez Ruiz, F.J.,  Moreno-Ventas Bravo, I., Jiménez Blas, F.: "Liquid-liquid interfacial properties of a symmetrical Lennard-Jones binary mixture". Journal of Chemical Physics. 143, 104706 (2015). Vol. 143, 104706 (2015). DOI 10/10.1063/1.4930276
NO The authors would like to acknowledge helpful discussions with J. M. Garrido, J. M. Miguez, M. M. Pineiro, and E. de Miguel. This work was supported by Ministerio de Economia y Competitividad through Grant No. FIS2013-46920-C2-1-P (confinanced with EU Feder funds). Further financial support from Junta de Andalucia and Universidad de Huelva is also acknowledged.
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026