External fields in conceptual density functional theory.

Area of Science:

• Theoretical Chemistry
• Computational Chemistry
• Quantum Chemistry

Background:

• The synthesis of novel molecules with unique properties necessitates advanced theoretical frameworks.
• Experimental conditions are increasingly complex, requiring extensions to existing chemical theories.

Purpose of the Study:

• To incorporate external variables such as electric fields, magnetic fields, mechanical forces, and confinement into conceptual DFT (CDFT).
• To develop new response functions within CDFT to describe chemical behavior under these external influences.

Main Methods:

• A finite field approach was employed to calculate the evolution of global and local descriptors.
• New response functions were derived, primarily using the first derivative with respect to the applied field.
• Applications were tested on atomic and molecular systems.

Main Results:

• Electric fields can induce enantioselectivity in descriptors like the Fukui function, relevant for oriented electric field chemistry.
• Magnetic fields affect atomic electronegativity and hardness, showing piecewise behavior and range compression at high field strengths, applicable to astrophysics.
• Mechanical forces alter diatomic properties by influencing equilibrium distances across different charge states.
• Confinement effects on atoms mirror increasing hardness under pressure, analogous to reduced polarizability.

Conclusions:

• External variables significantly impact chemical reactivity and properties, extending the predictive power of CDFT.
• Periodicity and interconnections between response functions are observed across various external field conditions.
• The extended CDFT framework provides insights for chemistry under extreme conditions and in oriented fields.