Journal of Computer-Aided Molecular Design

, Volume 24, Issue 4, pp 361–372 | Cite as

Predictions of hydration free energies from continuum solvent with solute polarizable models: the SAMPL2 blind challenge

  • Alexandre Meunier
  • Jean-François TruchonEmail author


This paper reports the results of our attempt to predict hydration free energies on the SAMPL2 blind challenge dataset. We mostly examine the effects of the solute electrostatic component on the accuracy of the predictions. The usefulness of electronic polarization in predicting hydration free energies is assessed by comparing the Electronic Polarization from Internal Continuum model and the self consistent reaction field IEF-PCM to standard non-polarizable charge models such as RESP and AM1-BCC. We also determine an optimal restraint weight for Dielectric-RESP atomic charges fitting. Statistical analysis of the results could not distinguish the methods from one another. The smallest average unsigned error obtained is 1.9 ± 0.6 kcal/mol (95% confidence level). A class of outliers led us to investigate the importance of the solute–solvent instantaneous induction energy, a missing term in PB continuum models. We estimated values between −1.5 and −6 kcal/mol for a series of halo-benzenes which can explain why some predicted hydration energies of non-polar molecules significantly disagreed with experiment.


EPIC Poisson-Boltzmann Implicit solvent Polarizability Hydration energy Solvation energy SAMPL2 



The authors thank Dr. Christopher Bayly from Merck Frosst Canada for his guidance on the 3-stage RESP procedure, for the informatics tools he gratefully provided to us and for his comments on the manuscript.

Supplementary material

10822_2010_9339_MOESM1_ESM.xls (124 kb)
Supplementary material 1 (XLS 123 kb)


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Merck Frosst CanadaKirklandCanada

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