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 density mixer (these components of the one-center charge density are set to the value corresponding to the present orbitals). Usually, it is not necessary to increase LMAXMIX, but the following cases are exceptions:

DFT+U calculations require, in many cases, an increase of LMAXMIX to 4 for d-electrons (or 6 for f-elements) to obtain fast convergence to the ground state.

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 not necessarily be 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.

SDFT calculations that consider noncollinear magnetism often require slow mixing of the spin density up to 4 for d-elements and up to 6 for f-elements to obtain fast convergence to the ground state.

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