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Title: Development of DPD coarse-grained models: From bulk to interfacial properties

Abstract

A new Bayesian method was recently introduced for developing coarse-grain (CG) force fields for molecular dynamics. The CG models designed for dissipative particle dynamics (DPD) are optimized based on trajectory matching. Here we extend this method to improve transferability across thermodynamic conditions. We demonstrate the capability of the method by developing a CG model of n-pentane from constant-NPT atomistic simulations of bulk liquid phases and we apply the CG-DPD model to the calculation of the surface tension of the liquid-vapor interface over a large range of temperatures. The coexisting densities, vapor pressures, and surface tensions calculated with different CG and atomistic models are compared to experiments. Depending on the database used for the development of the potentials, it is possible to build a CG model which performs very well in the reproduction of the surface tension on the orthobaric curve.

Authors:
; ; ;  [1];  [2]
  1. Institut de Chimie de Clermont-Ferrand, Université Blaise Pascal, Université Clermont Auvergne, BP 10448, F-63000 Clermont-Ferrand (France)
  2. (France)
Publication Date:
OSTI Identifier:
22679019
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 145; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; MOLECULAR DYNAMICS METHOD; SIMULATION; SURFACE TENSION; VAPOR PRESSURE

Citation Formats

Solano Canchaya, José G., Dequidt, Alain, E-mail: alain.dequidt@univ-bpclermont.fr, Goujon, Florent, Malfreyt, Patrice, and CNRS, UMR 6296, ICCF, F-63178 Aubiere. Development of DPD coarse-grained models: From bulk to interfacial properties. United States: N. p., 2016. Web. doi:10.1063/1.4960114.
Solano Canchaya, José G., Dequidt, Alain, E-mail: alain.dequidt@univ-bpclermont.fr, Goujon, Florent, Malfreyt, Patrice, & CNRS, UMR 6296, ICCF, F-63178 Aubiere. Development of DPD coarse-grained models: From bulk to interfacial properties. United States. doi:10.1063/1.4960114.
Solano Canchaya, José G., Dequidt, Alain, E-mail: alain.dequidt@univ-bpclermont.fr, Goujon, Florent, Malfreyt, Patrice, and CNRS, UMR 6296, ICCF, F-63178 Aubiere. Sun . "Development of DPD coarse-grained models: From bulk to interfacial properties". United States. doi:10.1063/1.4960114.
@article{osti_22679019,
title = {Development of DPD coarse-grained models: From bulk to interfacial properties},
author = {Solano Canchaya, José G. and Dequidt, Alain, E-mail: alain.dequidt@univ-bpclermont.fr and Goujon, Florent and Malfreyt, Patrice and CNRS, UMR 6296, ICCF, F-63178 Aubiere},
abstractNote = {A new Bayesian method was recently introduced for developing coarse-grain (CG) force fields for molecular dynamics. The CG models designed for dissipative particle dynamics (DPD) are optimized based on trajectory matching. Here we extend this method to improve transferability across thermodynamic conditions. We demonstrate the capability of the method by developing a CG model of n-pentane from constant-NPT atomistic simulations of bulk liquid phases and we apply the CG-DPD model to the calculation of the surface tension of the liquid-vapor interface over a large range of temperatures. The coexisting densities, vapor pressures, and surface tensions calculated with different CG and atomistic models are compared to experiments. Depending on the database used for the development of the potentials, it is possible to build a CG model which performs very well in the reproduction of the surface tension on the orthobaric curve.},
doi = {10.1063/1.4960114},
journal = {Journal of Chemical Physics},
number = 5,
volume = 145,
place = {United States},
year = {Sun Aug 07 00:00:00 EDT 2016},
month = {Sun Aug 07 00:00:00 EDT 2016}
}
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