Improved exchange-correlation potential for polarizability and dissociation in density functional theory.

Area of Science:

• Quantum Chemistry
• Computational Physics
• Materials Science

Background:

• Calculating molecular polarizabilities and dissociation behavior in electric fields is crucial for understanding chemical reactions and material properties.
• Existing methods often struggle with accuracy, particularly for open-shell systems and strong fields.

Purpose of the Study:

• To develop a novel approach for accurately predicting polarizabilities and dissociation in electric fields.
• To leverage the static limit of the Vignale-Kohn (VK) functional for improved ground-state properties.

Main Methods:

• Focusing on the response to the scalar part of the Vignale-Kohn (VK) response potential.
• Evaluating the ground-state properties of this specific potential.
• Comparing the performance against the full VK response density and semi-local functionals.

Main Results:

• The proposed potential exhibits improved ground-state properties compared to existing methods.
• The potential demonstrates correct qualitative behavior for polarizabilities, particularly for systems like the H(2) chain.
• Accurate dissociation of open-shell fragments in electric fields is achieved.

Conclusions:

• The novel approach based on the VK functional offers a significant improvement for calculating electric field effects on molecules.
• This method is expected to enhance predictions for molecular polarizabilities and dissociation, broadening its applicability in computational chemistry and physics.