NBANDS_WAVE

NBANDS_WAVE = [integer]

Default: NBANDS_WAVE	= NBANDSGW	for LALL_IN_ONE=.TRUE. and NBANDS<1
	= NBANDS	for LALL_IN_ONE=.TRUE. and NBANDS>0
	= NBANDSEXACT	for LALL_IN_ONE=.FALSE. and NBANDS<1
	= NBANDS	for LALL_IN_ONE=.FALSE. and NBANDS>0

Description: NBANDS_WAVE specifies the number of bands written to WAVECAR in the all-in-one mode of many-body perturbation theory calculations, i.e., ALGO=ACFDT[R], [EV]GW0[R], GWR.

Mind: available as of VASP.6.4.0

In the all-in-one mode, VASP automatically performs the necessary DFT steps prior to the many-body perturbation theory (MBPT) calculation, i.e. a DFT calculation with NBANDS, followed by an exact diagonalization of the Kohn-Sham Hamiltonian with NBANDSEXACT bands. Note, NBANDSEXACT is set by default to the maximum number of plane-waves given by the chosen energy cutoff for the orbitals ENCUT. In the all-in-one mode, the actual GW/RPA calculation is also performed with NBANDSEXACT bands. If NBANDS_WAVE is not set, all orbitals are written to WAVECAR, which potentially becomes huge in file size.

Tip: The NBANDS_WAVE tag can be used to limit the number of bands written to WAVECAR if LALL_IN_ONE=.TRUE.

The all-in-one mode is automatically enabled for ALGO=[EV]GW[0]R, RPA[R],ACFDT[R] if NBANDS is not set.

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