@article{10272/16292,
year = {2019},
url = {http://hdl.handle.net/10272/16292},
abstract = {A new Helmholtz free energy density functional is presented to predict the vapor-liquid interface of
chainlike molecules. The functional is based on the last version of the statistical associating fluid
theory for potentials of variable range for homogeneous Mie chainlike fluids (SAFT-VR Mie). Following
the standard formalism, the density functional theory (SAFT-VR Mie DFT) is constructed
using a perturbative approach in which the free energy density contains a reference term to describe
all the short-range interactions treated at the local level, and a perturbative contribution to
account for the attractive perturbation which incorporates the long-range dispersive interactions.
In this first work, we use a mean-field version of the theory in which the pair correlations are neglected
in the attractive term. The SAFT-VR Mie DFT formalism is used to examine the effect of
molecular chain length and the repulsive exponent of the intermolecular potential on density profiles
and surface tension of linear chains made up to six Mie (lr6) segments with different values
of the repulsive exponent of the intermolecular potential. Theoretical predictions from the theory
are compared directly with molecular simulation data for density profiles and surface tension of
Mie chainlike molecules taken from the literature. Agreement between theory and simulation data
is good for short-chain molecules at all thermodynamic conditions of coexistence considered.
Once the theory has proven that is able to predict the interfacial properties, and particularly interfacial
tension, the SAFT-VR Mie DFT formalism is used to predict the interfacial behavior of
two new coarse-grained models for carbon dioxide and water recently proposed in the literature.
In particular, the theoretical formalism, in combination with the coarse-grained models for carbon
dioxide and water, is able to predict the interfacial properties of these important substances in a
reasonable way.},
organization = {The authors thank helpful discussions with Carlos Avendaño andJosé Matías Garrido. We also acknowledge Centro de Supercom-putación de Galicia (CESGA, Santiago de Compostela, Spain) andMCIA (Mésocentre de Calcul Intensif Aquitain) of the Universitésde Bordeaux and Pau et Pays de l’Adour (France), for providingaccess to computing facilities and Ministerio de Economía, In-dustria y Competitividad through Grant with reference FIS2017-89361-C3-1-P co-financed by EU FEDER funds. Further financialsupport from Junta de Andalucía and Universidad de Huelva isalso acknowledged. J.A., J.M.M., and F.J.B. thankfully acknowl-edge the computer resources at Magerit and the technical supportprovided by the Spanish Supercomputing Network (RES) (ProjectQCM-2018-2-0042).},
publisher = {Royal Society of Chemistry},
title = {An accurate density functional theory for the vaporliquid interface of chain molecules based on the statistical associating fluid theory for potentials of variable range for Mie chainlike fluids},
doi = {10.1039/C9CP01597C},
author = {Algaba Fernández, Jesús and Míguez Díaz, José Manuel and Mendiboure, B. and Jiménez Blas, Felipe},
}