next up previous contents index
Next: LMIXTAU Up: meta-GGAs Previous: meta-GGAs   Contents   Index


LMAXTAU

LMAXTAU = .TRUE. | .FALSE.

Default    
LMAXTAU = 6 if LASPH = .TRUE.
  = 0 else

By means of LMAXTAU one can set the maximum $ l$-quantum number included in the PAW one-center expansion of the kinetic energy density. The PAW one-center expansion of the density has component up to and including $ L=2l_{\rm max}$, where $ l_{\rm max}$ is the $ l$-quantum number of the partial waves on the POTCAR file, with the highest angular moment. If the PAW one-center expansion of the density has component up to $ L$, then the one-center expansion of the kinetic energy density has components up to $ L+2$.

This means that as a rule of thumb, for $ s$-elements: LMAXTAU=2, for $ p$: LMAXTAU=4, and for $ d$: LMAXTAU=6. If you are willing to live with the computational costs, the default for LMAXTAU should be safe in all cases, except those involving $ f$-elements.

N.B.: It is recommended to set LASPH=.TRUE., when using meta-GGA functionals, since these often result in aspherical charge densities (see Sec. 6.44).


next up previous contents index
Next: LMIXTAU Up: meta-GGAs Previous: meta-GGAs   Contents   Index
N.B. Requests for support are to be addressed to: vasp.materialphysik@univie.ac.at