# SOC

Switch on or off spin-orbit coupling. Use SOC parameters from non-local pseudopotentials as given in Hartwigsen, Goedecker, Hutter, Eq.(18), (19), https://doi.org/10.1103/PhysRevB.58.3641, \(V_{\mu\nu}^{\mathrm{SOC}, (\alpha)} = (\hbar/2) \langle \phi_\mu | \sum_l \Delta V_l^\mathrm{SO}(\mathbf{r},\mathbf{r}') L^{(\alpha)} | \phi_\nu \rangle, \alpha = x, y, z\). [Edit on GitHub]

## Keywords

- SECTION_PARAMETERS

- ENERGY_WINDOW

## Keyword descriptions

SECTION_PARAMETERS: logical = F

  Lone keyword: `T`

  Controls the activation of the SOC calculation. [Edit on GitHub]

ENERGY_WINDOW: real = 4.00000000E+001 [eV]

  Usage: ENERGY_WINDOW 5.0

  Apply SOC only for states with eigenvalues in the interval \([\varepsilon_\mathrm{VBM}-E_\mathrm{window}/2, \varepsilon_\mathrm{CBM}+E_\mathrm{window}/2]\). Might be necessary to use for large systems to prevent numerical instabilities. [Edit on GitHub]