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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
How ambiguous is the local kinetic energy?
James S M Anderson1, Paul W Ayers, Juan I Rodriguez Hernandez
1Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1.
The Journal of Physical Chemistry. A
|July 1, 2010
Summary
This study clarifies ambiguities in local kinetic energy and electronic stress tensor calculations, crucial for understanding chemical bonds. New forms are derived, impacting chemical bonding and atoms-in-molecule analyses.
Area of Science:
- Quantum Chemistry
- Computational Chemistry
- Chemical Physics
Background:
- Local kinetic energy and electronic stress tensor are vital for analyzing chemical bonding, particularly covalent bonds.
- Existing methods face inherent ambiguities when interpreting these quantities.
Purpose of the Study:
- To clarify the inherent ambiguities in local kinetic energy and electronic stress tensor.
- To derive new, mathematically justified forms of these quantities.
- To discuss the implications for chemical bonding and atoms-in-molecule analyses.
Main Methods:
- Utilizing transformation properties of the stress tensor.
- Employing quasiprobability distributions.
- Applying the virial theorem from density-functional theory.
Main Results:
- An expansive family of local kinetic energy forms, including common choices, was derived.
- A corresponding family of local electronic stress tensors was also derived.
- Several mathematically justified but conceptually less useful local kinetic energy functions were identified.
Conclusions:
- The derived families offer a more comprehensive framework for analyzing chemical bonds.
- Understanding the implications of these forms is crucial for accurate atoms-in-molecule analysis.
- This work provides a refined toolkit for computational chemists studying molecular interactions.
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