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Quantitative Hardness Measurement by Instrumented AFM-indentation
Published on: November 22, 2016
Local hardness equalization and the principle of maximum hardness
José L Gázquez1, Alberto Vela, Pratim K Chattaraj
1Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, México, D. F. 09340, Mexico. jlgm@xanum.uam.mx
The Journal of Chemical Physics
|June 14, 2013
Summary
The principle of maximum hardness dictates that charge transfer is inversely proportional to molecular hardness. Additional energy terms explain deviations from maximum hardness, with the dual descriptor crucial for hardness equalization.
Area of Science:
- Quantum Chemistry
- Chemical Physics
Background:
- The chemical potential, hardness, and hyperhardnesses equalization principles are fundamental concepts in density functional theory.
- Understanding molecular interactions and stability is crucial in chemistry and materials science.
Purpose of the Study:
- To investigate the relationship between charge transfer and molecular hardness using equalization principles.
- To explain deviations from maximum hardness and minimum energy points in molecular interactions.
- To elucidate the role of the dual descriptor in hardness equalization.
Main Methods:
- Application of chemical potential, hardness, and hyperhardnesses equalization principles.
- Analysis of interaction energy among molecular fragments.
- Examination of the dual descriptor's influence on hardness equalization.
Main Results:
- The leading term of charge transfer is directly proportional to the negative of the molecule's ground-state hardness.
- Additional interaction energy terms account for deviations between maximum hardness and minimum energy points.
- The dual descriptor significantly contributes to hardness equalization.
Conclusions:
- The principle of maximum hardness provides a key insight into charge transfer phenomena.
- Molecular fragment interactions are influenced by changes in external potentials, leading to energy deviations.
- The dual descriptor is essential for understanding and predicting hardness equalization in molecules.
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