An approach to computing electrostatic charges for molecules

Authors

  • U. Chandra Singh,

    1. School of Pharmacy, Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143
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  • Peter A. Kollman

    Corresponding author
    1. School of Pharmacy, Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143
    • School of Pharmacy, Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143
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Abstract

We present an approach for deriving net atomic charges from ab initio quantum mechanical calculations using a least squares fit of the quantum mechanically calculated electrostatic potential to that of the partial charge model. Our computational approach is similar to those presented by Momany [J. Phys. Chem., 82, 592 (1978)], Smit, Derissen, and van Duijneveldt [Mol. Phys., 37, 521 (1979)], and Cox and Williams [J. Comput. Chem., 2, 304 (1981)], but differs in the approach to choosing the positions for evaluating the potential. In this article, we present applications to the molecules H2O, CH3OH, (CH3)2O, H2CO, NH3, (CH3O)2POmath image, deoxyribose, ribose, adenine, 9-CH3 adenine, thymine, 1-CH3 thymine, guanine, 9-CH3 guanine, cytosine, 1-CH3 cytosine, uracil, and 1-CH3 uracil. We also address the question of inclusion of “lone pairs,” their location and charge.

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