Advances in correlated electronic structure methods for solids, surfaces, and nanostructures

Area of Science:

• Solid-state physics and chemistry
• Computational materials science
• Quantum mechanical modeling

Background:

• Electronic structure calculations for solids have a long history.
• Solid-state quantum techniques have recently matured for routine application.
• Quantum chemistry methods for molecules serve as a benchmark for reliability.

Purpose of the Study:

• To introduce chemists to first-principles methods for materials science.
• To outline the advantages and disadvantages of various computational techniques.
• To provide atomic-scale insight into bulk materials, interfaces, and nanostructures.

Main Methods:

• Density Functional Theory (DFT): A ubiquitous and often sufficient method, particularly for metals.
• Extensions: DFT + U and hybrid DFT address self-interaction errors in semiconductors and correlated materials.
• Many-Body Green's Function (GW, Bethe-Salpeter): Methods for calculating excited-state properties.
• Quantum Monte Carlo (QMC): An exact theory with challenges in calculating forces for structure optimization and dynamics.
• Embedding Theories: Techniques for locally refining quantum treatments to enhance accuracy.

Main Results:

• DFT is a workhorse for electronic structure calculations, especially for metallic systems.
• Advanced DFT variants and Green's function methods are crucial for specific material classes and excited states.
• QMC and embedding theories offer alternative or complementary approaches with distinct strengths and limitations.

Conclusions:

• First-principles methods provide powerful tools for understanding materials at the atomic scale.
• The choice of method depends on the material system and the properties of interest.
• These computational techniques are becoming increasingly accessible and routine for chemists.