LMAXMIX
LMAXMIX = [integer]
Default: LMAXMIX = 2
Description: LMAXMIX controls up to which l-quantum number the one-center PAW charge densities are passed through the charge density mixer and written to the CHGCAR file.
Higher l-quantum numbers (l>LMAXMIX) are not handled by the mixer (these components of the one-center charge density are simply set to the value corresponding to the present orbitals). Usually, it is not required to increase LMAXMIX, but the following two cases are exceptions:
- DFT+U calculations require in many cases an increase of LMAXMIX to 4 for d-electrons (or 6 for f-elements) in order to obtain fast convergence to the groundstate.
- The CHGCAR file will contain the one-center PAW occupancy matrices up to LMAXMIX. When the CHGCAR file is read and kept fixed in the course of the calculations (ICHARG=11), the results will be not necessarily identical to a self-consistent run. The deviations will be large for DFT+U calculations. For the calculation of band structures within the DFT+U approach, it is strictly required to increase LMAXMIX to 4 for d-elements and to 6 for f-elements.