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arXiv · 1302.2848

Molecular Density Functional Theory of Water

Guillaume Jeanmairet·Maximilien Levesque·Rodolphe Vuilleumier·Daniel Borgis
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Abstract

Three dimensional implementations of liquid state theories offer an efficient alternative to computer simulations for the atomic-level description of aqueous solutions in complex environments. In this context, we present a (classical) molecular density functional theory (MDFT) of water that is derived from first principles and is based on two classical density fields, a scalar one, the particle density, and a vectorial one, the multipolar polarization density. Its implementation requires as input the partial charge distribution of a water molecule and three measurable bulk properties, namely the structure factor and the k-dependent longitudinal and transverse dielectric constants. It has to be complemented by a solute-solvent three-body term that reinforces tetrahedral order at short range. The approach is shown to provide the correct three-dimensional microscopic solvation profile around various molecular solutes, possibly possessing H-bonding sites, at a computer cost two-three orders of magnitude lower than with explicit simulations.

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Guillaume Jeanmairet, Maximilien Levesque, Rodolphe Vuilleumier, Daniel Borgis. 2013-02-12. Molecular Density Functional Theory of Water. https://doi.org/10.1021/jz301956b

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