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Using multipole point charge distributions to provide the electrostatic potential in the variational explicit
Hannah R Leverentz1, Jiali Gao, Donald G Truhlar
1Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, MN 55455-0431, USA.
Theoretical Chemistry Accounts
|March 16, 2013
Summary
This study introduces a multipole variational explicit polarization (X-Pol) potential, enhancing polarization calculations by using multipole point charge distributions instead of Mulliken charges for improved accuracy in computational chemistry.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Molecular Modeling
Background:
- The variational explicit polarization (X-Pol) potential is a method used to model molecular polarization.
- Previous formulations relied on Mulliken charges, which represent a monopole approximation.
Purpose of the Study:
- To modify the variational X-Pol potential for enhanced accuracy.
- To implement a more sophisticated representation of electron densities in polarization calculations.
Main Methods:
- The study modifies the equations for the variational X-Pol potential.
- Atom-centered multipole point charge distributions are used to represent electron densities.
- Both the optimized monomer and external monomers utilize this multipole representation.
Main Results:
- The new formulation, termed the "multipole variational X-Pol potential," improves upon the original method.
- It avoids the monopole truncation inherent in using Mulliken charges.
- This leads to a more accurate representation of electrostatic interactions during optimization.
Conclusions:
- The multipole variational X-Pol potential offers a more rigorous approach to calculating molecular polarization.
- This advancement is expected to improve the accuracy of quantum chemical calculations involving polarization effects.
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