DFT Corrections (3 sub-skills: hubbard-u, spin-orbit-coupling, vdw-correction)
Beyond-standard-DFT corrections for improved accuracy in specific material classes. These corrections address known deficiencies of semi-local DFT functionals (GGA/LDA) and should be applied when the physics demands it.
| Sub-Skill | Directory | Use Case | QE Keywords |
|---|---|---|---|
| Hubbard U (DFT+U) | hubbard-u/ | Strongly correlated systems: transition metal oxides, f-electron systems, Mott insulators | lda_plus_u, Hubbard_U(i), hp.x |
| Van der Waals Corrections | vdw-correction/ | Layered materials, molecular crystals, adsorption, MOFs, weakly bound systems | vdw_corr, input_dft='vdw-df' |
| Spin-Orbit Coupling | spin-orbit-coupling/ | Heavy elements, topological insulators, Rashba splitting, magnetic anisotropy | noncolin, lspinorb, rel pseudopotentials |
Is your system strongly correlated (open d/f shells)?
YES --> Use DFT+U (hubbard-u/)
NO --> Standard DFT may be fine
Are van der Waals interactions important (layered, molecular, adsorption)?
YES --> Use vdW correction (vdw-correction/)
NO --> Standard DFT may be fine
Does your system contain heavy elements (Z > 50) or need spin-orbit physics?
YES --> Use SOC (spin-orbit-coupling/)
NO --> Scalar-relativistic PP is sufficient
Note: These corrections are NOT mutually exclusive. For example, a transition metal dichalcogenide may require both vdW corrections (layered structure) and SOC (heavy chalcogen). A correlated oxide surface with adsorbed molecules may need DFT+U and vdW together.
pw.x, pp.x, ph.x, hp.x)pymatgen, ASE, numpy, matplotlib for post-processing