Charge Transfer Interaction between Ab Initio and Effective Fragment Potential Molecules.
Megan R Schlinsog1, Mark S Gordon1
1Department of Chemistry and Ames National Laboratory, Iowa State University, Ames, Iowa 50011, United States.
Journal of Chemical Theory and Computation
|July 6, 2026
Summary
This study introduces a new charge transfer method for Quantum Mechanics (QM) and Effective Fragment Potential (EFP) molecular interactions. This approach significantly enhances the accuracy of calculating intermolecular interaction energies.
Area of Science:
- Computational Chemistry
- Quantum Mechanics
- Molecular Modeling
Background:
- Accurate calculation of intermolecular interactions is crucial in chemistry.
- Existing methods like QM-EFP have limitations in capturing certain interaction components.
- Charge transfer is a key factor influencing molecular interactions.
Purpose of the Study:
- To derive and implement the charge transfer contribution within the QM-EFP framework.
- To assess the impact of charge transfer on the accuracy of QM-EFP interaction energy calculations.
- To improve the reliability of computational methods for studying molecular systems.
Main Methods:
- Derivation of the charge transfer term using second-order perturbation theory.
- Implementation of the derived term into the GAMESS computational chemistry software.
- Validation against benchmark interaction energies from the S22 and S66 datasets.
Main Results:
- The charge transfer contribution was successfully derived and implemented in the QM-EFP method.
- Incorporating charge transfer significantly improved the accuracy of QM-EFP interaction energies.
- The enhanced method showed better agreement with benchmark data.
Conclusions:
- The charge transfer term is essential for accurate QM-EFP intermolecular interaction energy calculations.
- The developed QM-EFP method with charge transfer offers a more reliable approach for molecular modeling.
- This advancement benefits computational studies requiring precise interaction energy predictions.
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