Hydrophobic Solvation in Liquid Water Via Car-Parrinello Molecular Dynamics: Progress and First Results
Solvation of apolar substances in liquid water plays a crucial role in “wet chemistry” as well as in biochemistry due to the relation to hydrophobicity effects. However, knowledge of the microscopic details of structure and dynamics at such solute-water “interfaces” is rather limited. The object of this study is a single hydrogen radical in water at ambient conditions. This system was chosen, because it is known experimentally that the diffusion of H in water is much faster than the self-diffusion of water itself and only marginally slower than the fast Grotthuss diffusion of H+ in water. This paradox awaits an explanation, in particular since pioneering classical molecular dynamics simulations predict a clathrate-like cage and do not confirm fast diffusion, probably because of insufficiently accurate model potentials. This limitation can be circumvented by using Car—Parrinello molecular dynamics, where the interactions are derived from density functional electronic structure calculations.
KeywordsWater Molecule Liquid Water Electron Localization Function Hydrogen Radical Hydrophobic Solvation
Unable to display preview. Download preview PDF.
- 3.J. Hutter and D. Marx: Ab Initio Molecular Dynamics: Theory and Implementation. In J. Grotendorst, editor, Modern Methods and Algorithms of Quantum Chemistry. John von Neumann Institute for Computing. Jülich (2000) 301–450Google Scholar