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Relationships between the third-order reactivity indicators in chemical density-functional theory
Carlos Cárdenas1, Eleonora Echegaray, Debajit Chakraborty
1Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
The Journal of Chemical Physics
|July 2, 2009
Summary
This study unifies reactivity indicators across different chemical system pictures. It reveals a new link between hyperpolarizability and electron density sensitivity using the dual descriptor.
Area of Science:
- Theoretical Chemistry
- Quantum Chemistry
- Chemical Reactivity Theory
Background:
- Understanding chemical reactivity is crucial for predicting molecular behavior.
- Existing models for reactivity indicators often operate within specific theoretical frameworks (closed, open, or density systems).
Purpose of the Study:
- To derive unified relationships between third-order reactivity indicators in different theoretical pictures.
- To establish a novel connection between molecular hyperpolarizability and electron density sensitivity.
Main Methods:
- Derivation of relationships between reactivity indicators in closed [N, v(r)], open [mu, v(r)], and density [rho(r)] systems.
- Utilizing the dual descriptor as a unifying concept.
Main Results:
- Established new links between third-order reactivity indicators, unifying previous findings.
- Demonstrated a connection between the third-order energy response to density changes and the quadratic density response to external potential changes.
- The dual descriptor emerged as a central element in the derived formulas.
Conclusions:
- The derived relationships provide a more comprehensive understanding of chemical reactivity.
- The findings link molecular electronic properties (hyperpolarizability) to the system's response to external perturbations.
- The dual descriptor offers a powerful tool for unifying diverse reactivity concepts.
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