Water Density Fluctuations Relevant to Hydrophobic Hydration are Unaltered by Attractions
arXiv:1410.1614 · doi:10.1063/1.4905009
Abstract
An understanding of density fluctuations in bulk water has made significant contributions to our understanding of the hydration and interactions of idealized, purely repulsive hydrophobic solutes. To similarly inform the hydration of realistic hydrophobic solutes that have dispersive interactions with water, here we characterize water density fluctuations in the presence of attractive fields that correspond to solute-water attractions. We find that when the attractive field acts only in the solute hydration shell, but not in the solute core, it does not significantly alter water density fluctuations in the solute core region. We further find that for a wide range of solute sizes and attraction strengths, the free energetics of turning on the attractive fields in bulk water are accurately captured by linear response theory. Our results also suggest strategies for more efficiently estimating hydration free energies of realistic solutes in bulk water and at interfaces.
11 pages + 3 pages of supplementary material
References in corpus (10)
- Canonical sampling through velocity-rescaling
- Role of water in Protein Aggregation and Amyloid Polymorphism
- The molecular structure of the interface between water and a hydrophobic substrate is liquid-vapor like
- Effects of lengthscales and attractions on the collapse of hydrophobic polymers in water
- Local molecular field theory for effective attractions between like charged objects in systems with strong Coulomb interactions
- Interplay of local hydrogen-bonding and long-ranged dipolar forces in simulations of confined water
- Local molecular field theory for the treatment of electrostatics
- Dissecting Hydrophobic Hydration and Association
- Water Density Fluctuations Relevant to Hydrophobic Hydration are Unaltered by Attractions
- Segue Between Favorable and Unfavorable Solvation