RPBE calculations

[busnengo]

I want to run RPBE calculations.

i) is the seting of the GGA tag (=RP) in the INCAR file enough or other input should be modified or introduced.
ii) Is there a pseudopotential (POTCAR LDA, POTCAR GGA-PW91 or POTCAR GGA-PBE) specially suitable for such a calculation.
iii) Will RPBE XC functional be treated in a fully selfconsistent way by Vasp or it will only introduce a correction to the total energy at the end using the density obtained with the XC functional corresponding to the POTCAR used?
iv) Migth the results be affected by significant errors due to the use of a XC functional that is not the same as that used to generate the pseudopotential?

Thanks in advance.

Fabio

[tjf]

The prevailing wisdom in pseudopotential calculations, as far as I have been able to determine, is that GGA pseudopotentials are all much the muchness. Or at least that the error introduced by using the "wrong" pseudopotential (generated with some other GGA functional) is similar to the error inherent in using pseudopotentials in the first place.

I await a comment from someone who knows, whether using the PBE PAW POTCARs is the recommended thing to do when doing RPBE calculations. (That is, whether my interpretation of the prevailing wisdom in pseudopotential calculations translates to PAW calculations.)

[tjf]

Does no-one have any other educated input on this question? (Looks significantly at admin... ;-)



<span class='smallblacktext'>[ Edited Tue Jun 06 2006, 12:32PM ]</span>

[admin]

yes, to use RPBE XC, it is best to start from a PAW-PBE POTCAR and set GGA=RP in INCAR. The XC-part ot the potential is treated self-consistently within the RPBE formalism then.