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Block deformation analysis: Density matrix blocks as intramolecular deformation density.
Isa Ravaei1, Seyed Mohammad Azami1
1Chemistry Department, College of Sciences, Yasouj University, Yasouj, Iran.
Journal of Computational Chemistry
|August 27, 2020
Summary
Block deformation analysis quantifies intramolecular interactions by analyzing atomic orbital deformation density. This method reveals charge displacement and reorganization, offering a new bonding index for chemical systems.
Area of Science:
- Quantum chemistry
- Computational chemistry
- Materials science
Background:
- Understanding intramolecular interactions is crucial for predicting molecular properties.
- Existing methods for analyzing electron density and bonding have limitations.
Purpose of the Study:
- Introduce a novel method, block deformation analysis, for quantifying intramolecular interactions.
- Develop a new approach to extract and analyze deformation density.
Main Methods:
- Utilize density matrix blocks in terms of natural atomic orbitals.
- Perform eigenanalysis on extracted deformation density.
- Apply the method to small molecules, carbon allotropes, and complex systems.
Main Results:
- Successfully extracted deformation density and identified interacting subsystems.
- Eigenanalysis yielded eigenvalues (displaced charge) and eigenorbitals (charge reorganization).
- Results showed high correlation with delocalization and Wiberg bond indices.
Conclusions:
- Block deformation analysis provides a comprehensive understanding of intramolecular interactions.
- Eigenvalues from this analysis can serve as a reliable bonding index.
- The method is versatile, applicable to diverse chemical structures.
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