Double-hybrid density functionals: merging wavefunction and density approaches to get the best of both worlds

Area of Science:

• Computational chemistry
• Quantum chemistry
• Theoretical chemistry

Background:

• Hybrid density functionals are widely used.
• Double-hybrid density functionals emerge from the Adiabatic Connection Method.
• These methods combine accuracy, robustness, and reliability.

Purpose of the Study:

• To review the rise of double-hybrid density functionals.
• To highlight their applications and extensions.
• To discuss their future role in computational chemistry.

Main Methods:

• Review of existing literature on double-hybrid density functionals.
• Discussion of the Adiabatic Connection Method.
• Analysis of applications in chemical systems.

Main Results:

• Double-hybrid density functionals provide unprecedented accuracy.
• They show large robustness and reliability.
• Recent applications cover chemical systems, non-covalent interactions, and excitation energies.

Conclusions:

• Double-hybrid density functionals are leading actors in computational chemistry.
• Despite higher computational cost, they are vital for future discoveries.
• These methods pave the way for advances in understanding chemical phenomena.