The Potential of Mean Force concept for bridging (length and time) scales in the modeling of complex porous materials

¹ Department of Civil and Environmental Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
² Centre Interdisciplinaire de Nanosciences de Marseille, Aix-Marseille Université, CNRS, Campus de Luminy, Marseille, France
³ <MSE> 2The joint CNRS / MIT / Aix-Marseille Université laboratory, MIT, Cambridge, MA 02139, USA
⁴ Laboratoire Navier, Université Paris-Est, CNRS, ENPC, IFSTTAR, Marne-la-Vallée, France

^* Corresponding author: pellenq@mit.edu

Published online: 30 June 2017

Abstract

We introduce the concept of Potential of Mean Force, PMF, as a way to implement upscaling modeling from the nano-scale to micron-scale. A PMF is a free energy function representing in an effective way the interactions between objects (cement hydrates, clay platelets, etc.) at thermodynamics conditions. The PMF is therefore the key piece of information allowing to coarse-grained Physical-Chemistry information in a meso-scale model formulation. The use of PMF offers a huge computational advantage as it allows a straight up-scaling to the meso-scale while keeping essential interactions information that are the hallmark of Physical-Chemistry processes. Such a coarse-grained modeling integrates atomistic response into inter-particle potentials that fully propagate molecular scale information all the way to the meso-scale.