Development of exchange-correlation functionals with minimal many-electron self-interaction error.

Area of Science:

• Quantum Chemistry
• Computational Materials Science

Background:

• Many-electron self-interaction error is a significant challenge in electronic structure calculations.
• Accurate prediction of thermochemistry and electronic properties requires robust exchange-correlation functionals.

Purpose of the Study:

• To develop novel exchange-correlation functionals addressing many-electron self-interaction error.
• To evaluate the performance of these new functionals using both thermochemical data and fractional electron systems.

Main Methods:

• Development of new exchange-correlation functionals incorporating Coulomb-attenuated exchange.
• Utilizing adiabatic connection theory with short-range and long-range splittings.
• Assessing functional performance on systems with fractional numbers of electrons and standard thermochemical tests.

Main Results:

• The new functionals demonstrate good performance on thermochemical benchmarks.
• A significantly improved description of total energy as a function of electron number was achieved.
• A substantial reduction in many-electron self-interaction error was observed.

Conclusions:

• The developed functionals effectively mitigate many-electron self-interaction error.
• These functionals offer a more accurate description of electronic systems, particularly concerning electron number dependency.
• The approach provides a promising avenue for improving the accuracy of density functional theory calculations.