Conceptual density functional theory for interacting species

Area of Science:

• Theoretical Chemistry
• Computational Chemistry
• Chemical Physics

Background:

• Chemical reactivity is complex, involving interactions between molecules.
• Understanding these interactions requires robust theoretical frameworks.
• Conceptual Density Functional Theory (CDFT) offers a powerful lens for studying chemical systems.

Purpose of the Study:

• To translate first-order perturbation theory into the framework of CDFT.
• To elucidate the roles of chemical potential, hardness, Fukui function, and dual descriptor in chemical reactivity.
• To connect these CDFT descriptors to frontier orbital theory and validate theoretical predictions.

Main Methods:

• Application of first-order perturbation theory to interacting species.
• Translation of perturbation effects into CDFT language.
• Analysis of chemical potential, hardness, Fukui function, and dual descriptor.
• Validation using the "|Δμ| big is good" rule and specific case studies.

Main Results:

• Perturbation effects on chemical potential and hardness are expressible within CDFT.
• The covalent contribution to interaction energy can be quantified using CDFT descriptors.
• A strong link is established between CDFT, frontier orbital theory, and chemical reactivity.
• Perturbed descriptors offer insights into reactant approach and dominant reaction effects.

Conclusions:

• CDFT provides a robust framework for understanding chemical reactivity at both global and local levels.
• Frontier orbital theory plays a fundamental role, validated by CDFT principles.
• The study validates theoretical predictions from first principles, enhancing our understanding of reaction mechanisms.