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On-Top Ratio for Atoms and Molecules
Rebecca K Carlson1, Donald G Truhlar1, Laura Gagliardi1
1Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , Minneapolis , Minnesota 55455-0431 , United States.
The Journal of Physical Chemistry. A
|August 23, 2019
Summary
The on-top ratio (R) helps analyze chemical bonds. Its partial derivative indicates covalent bond breaking in molecules like ethylene.
Area of Science:
- Quantum Chemistry
- Chemical Bonding Theory
Background:
- Understanding chemical bonds is fundamental to chemistry.
- Existing methods for bond analysis can be complex.
Purpose of the Study:
- To introduce and explore the utility of the on-top ratio (R) as a tool for analyzing chemical bonds.
- To demonstrate R's effectiveness in distinguishing various bond types and identifying bond breaking.
Main Methods:
- Calculation of the on-top ratio (R) using electron densities.
- Analysis of the partial derivative of R with respect to interatomic distance.
- Application to diatomic molecules and ethylene.
Main Results:
- The on-top ratio (R) effectively differentiates between covalent, polar covalent, ionic, and weak interactions.
- The partial derivative of R serves as a reliable indicator of covalent bond dissociation.
- R exhibits local maxima corresponding to electron shells under electron correlation.
Conclusions:
- The on-top ratio (R) is a valuable and accessible metric for characterizing chemical bonds.
- R and its derivatives offer new insights into bond dynamics and electronic structure.
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