Accurate calculation of pKa values is required for many organic and biological applications especially those related to protein and drug molecules. Here we present a continuum solvation model termed Fuzzy-Border (FB) in its first-order implementation. It is used to predict accurately the pKa values of eleven substituted phenol and hydration energies of other compounds. The solutes were modeled with the OPLS-AA force field. The overall average unsigned error was equal to 0.40 pH units in the calculated acidity constant values and 0.076 kcal/mol in the solvation energies of the molecules. This model uses fixed-position grid points to limit the noise and employs either second- or first-order approximation for the solvent polarization, depending on a particular implementation. Although these results were produced by fitting to the experimental data, they prove the ability of the model to yield accurate results that justifies its use in further simulations of organic and biophysical systems.

Developing first-order continuum Fuzzy-Border solvation model and applying for calculating pKa values of substituted phenols and hydration energies of small molecules

244th National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.