论文信息 - Errors in free-energy perturbation calculations due to neglecting the conformational variation of atomic charges

Errors in free-energy perturbation calculations due to neglecting the conformational variation of atomic charges

Abstract There is much concern about the accuracy of free-energy perturbation calculations. Here we have investigated the problem of ignoring the conformational variation of atomic charges by calculating the difference in the free energy of hydration between ethanol and propanol and comparing the results obtained for conformationally transferable charges with those obtained using conventional atomic charges and experiment. The results show that the common practice of ignoring the conformational variation of atomic charges may lead to serious errors which can dominate over all other errors.

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