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Related Experiment Video

Updated: Jun 24, 2026

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

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Self-consistent charge equilibration method and its application to Au13Na(n) (n = 1,10) clusters.

Min Zhang¹, René Fournier

¹Department of Physics & Astronomy, York University, Toronto, Ontario, Canada M3J 1P3.

The Journal of Physical Chemistry. A

|March 27, 2009

Summary

We enhanced the charge equilibration method (QEq) with higher-order terms, creating a new SMP/QEq potential for accurate molecular energy and charge calculations. This method enables reliable geometry optimizations and ionization energy predictions.

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Last Updated: Jun 24, 2026

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Spatial Separation of Molecular Conformers and Clusters

Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Area of Science:

Computational Chemistry
Quantum Chemistry
Molecular Modeling

Background:

The charge equilibration (QEq) method is widely used for calculating atomic charges in molecules.
Existing QEq methods may have limitations in accuracy for certain molecular systems.
Accurate charge distributions are crucial for predicting molecular properties and reactivity.

Purpose of the Study:

To improve the accuracy and reliability of the charge equilibration method.
To develop a new computational potential for molecular modeling.
To enable more precise geometry optimizations and ionization energy calculations.

Main Methods:

Modified the charge equilibration (QEq) method by incorporating third and fourth-order terms.
Developed a new potential by combining the modified QEq with a scaled Morse potential (SMP), termed SMP/QEq.
Validated the SMP/QEq method against high-level theoretical calculations and experimental data.

Main Results:

The modified QEq method provides a self-consistent scheme for determining molecular charges and total energy.
The SMP/QEq potential enables realistic geometry optimizations and accurate charge distributions.
Calculated ionization energies using SMP/QEq show good agreement with experimental and theoretical results.

Conclusions:

The SMP/QEq method offers a significant improvement over existing QEq approaches.
The established connection between Density Functional Theory (DFT) and SMP/QEq provides theoretical insights and avenues for further refinement.
SMP/QEq is a promising tool for molecular modeling, charge distribution analysis, and predicting ionization energies.