Connection between nuclear and electronic Fukui functions beyond frontier molecular orbitals

Area of Science:

• Theoretical Chemistry
• Quantum Chemistry
• Chemical Reactivity Theory

Background:

• Fukui functions are crucial for predicting chemical reactivity.
• Existing models often focus on frontier molecular orbitals.
• Understanding nuclear contributions to reactivity is an ongoing challenge.

Purpose of the Study:

• To establish a connection between nuclear and electronic Fukui functions beyond the frontier molecular orbital approximation.
• To derive expressions for average nuclear Fukui functions.
• To interpret nuclear Fukui functions in terms of local nucleophilicity and electrophilicity variations.

Main Methods:

• Utilizing the relationship between average local ionization energy and average local electron affinity with electronic Fukui functions.
• Developing a theoretical framework connecting nuclear and electronic Fukui functions.
• Applying the frontier molecular orbital approximation to derive specific expressions.

Main Results:

• A novel connection between nuclear and electronic Fukui functions is established.
• Expressions for average nuclear Fukui functions are derived, representing variations in nucleophilicity/electrophilicity.
• Nuclear Fukui functions are expressed in terms of atom-condensed electronic Fukui functions, indicating local reactivity.

Conclusions:

• The derived nuclear Fukui functions offer a new interpretation of chemical reactivity.
• This approach extends beyond frontier molecular orbitals, incorporating nuclear displacements.
• The findings have potential applications in studying molecular vibrations, reaction coordinates, and other dynamic chemical processes.