Molecular Theory of Hydration at Different Temperatures

Solvation
plays an important role in diverse chemical processes
ranging from reaction kinetics to molecular recognition, solubility,
and phase separations. Despite a long-history of theoretical exploration,
quantitative prediction of solvation remains a theoretical challenge
without relying on the macroscopic properties of the solvent as an
input. Here we present a molecular density functional theory that
provides a self-consistent description of the solvation structure
and thermodynamic properties of small organic molecules in liquid
water at different temperatures. Based on the solute configuration
and force-field parameters generated from first-principles calculations,
the theoretical predictions are found in good agreement with experimental
data for the hydration free energies of 197 organic molecules in a
temperature range from 0 to 40 °C. In addition to calibration
with experimental results, the theoretical predictions are compared
with recent molecular dynamics simulations for the hydration of five
highly explosive nitrotoluenes. This work demonstrates the potential
of the classical density functional theory for high-throughput prediction of solvation
properties over a broad range of temperatures.