Optimal charge and charge response determination through conformational space: global fitting scheme for
1Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan. ishida@ims.ac.jp
The Journal of Physical Chemistry. A
|July 10, 2008
Summary
A new global fitting scheme accurately estimates partial charge and charge response kernels (CRKs) from conformational data. This method effectively models polarization effects in molecules, even with many conformers.
Area of Science:
- Computational Chemistry
- Molecular Modeling
- Quantum Chemistry
Background:
- Accurate molecular modeling requires capturing electronic polarization effects.
- Partial charge and charge response kernels (CRKs) are crucial for describing polarization.
- Existing methods may struggle with complex systems and large conformational spaces.
Purpose of the Study:
- To develop a robust global fitting scheme for estimating partial charge and CRKs.
- To validate the method's performance and accuracy across various molecular systems.
- To investigate the influence of molecular conformation and interactions on polarization.
Main Methods:
- Least-squares global fitting derived from conformational space sampling data.
- Application to 1-butanol, 1-pentanol, and 1-dodecanol systems.
- Analysis of electronic structure changes and CRK fluctuations.
Main Results:
- The global fitting scheme accurately estimates partial charge and CRKs.
- Intramolecular polarization is influenced by hydrogen bonding, which the method captures.
- Nonlocality in polarization within alkyl chains and CRK fluctuations were observed.
Conclusions:
- The proposed global fitting scheme is effective for modeling polarization effects.
- It is applicable to large molecular systems with diverse conformers.
- Enables the development of molecular models with explicit polarization considerations.
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