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`LMAXFOCKAE `

`LMAXFOCKAE`= [integer] (maximum L quantum number for accurate charge augmentation in Hartree-Fock routines)

Default for GW type calculations: `LMAXFOCKAE`= 4

For accurate QP eigenvalues of systems with localized electrons,
the flag `LMAXFOCKAE` must be set.
Usually VASP restores only the *moments* of the all electron charge density on the
plane wave grid up to a certain radial quantum number .
If `LMAXFOCKAE` is set, the *shape* of the charge density is restored
accurately on the plane wave grid up to a typical plane wave energy of 100 eV.
Beyond that cutoff the polarizability is usually very small (),
necessitating no accurate treatment.

Restoring the charge density on the plane wave grid with high precision
allows to obtain accurate QP energies, even though the one-center-terms
are not implemented in VASP for the GW case. The flag must be selected
for GW calculations involving transition metals (`LMAXFOCKAE`=4)
and/or first row elements (`LMAXFOCKAE`=2).
See also Secs. 6.71.6 and 6.71.7.
In the present code version the default for `LMAXFOCKAE` is 4, sufficient
for most materials.

Even higher precision may be obtained by additionally setting
`NMAXFOCKAE`= 2 (the default is `NMAXFOCKAE`= 1).
This allows to restore the AE-charge density up to a typical plane wave energy of 400 eV.
In most cases, differences between `NMAXFOCKAE`= 1 and `NMAXFOCKAE`= 2
are, however, very small.

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N.B. Requests for support are to be addressed to: vasp.materialphysik@univie.ac.at