[Pw_forum] compatibility between pseudopotential choice and input_dft token

[Cristian Degli Esposti Boschi]

 >> Or a GGA (say C.pbe-mt_fhi.UPF in my case)
 > All the vdW corrections (semiempirical DFTD2 included, london=.true.,
 > in &system) are well tested with a given kind of xc functional. This
 > is often discussed in the related papers. If you are not certain of >
 > the functional recipes, look into the funct.f90 file. But this is not
 > a hard limit. You may build your own functional, including vdW. I've
 > tested, with PBE pseudopotentials, an hybrid+vdW functional time ago
 > ('sla+pw+hse+vdw1'), with good results on molecule-surface
 > interactions.


Thanks for the answers; now my question can be more specific:
suppose I want to use a pseudopotential built constructed for PBE
(say C.pbe-mt_fhi.UPF in my case). If I set input_dft = "vdw-df",
that means "sla+pw+rpb+vdw1",
as far as I can see the gradient
correction on exchange is revPBE and not PBE (third index is 4), and 
also there is no gradient correction on correlation (fourth index is 0).
Is this compatible with a PBE pseudopotential file that, if used without
vdw-df specification, would report an exchange-correlation scheme
"sla+pw+pbx+pbc" (1 4 3 4 0)?

Or, should I set something like "sla+pw+pbx+pbc+vdw1" in order
to be consistent with the PBE pseudopotential file?

The same question may hold for Cooper's variant (c09x instead of rpb above)

The question is on how the code works internally; at the beginning
of the output there is a warning "Any further DFT definition will be 
discarded", and I wonder what it means exactly...

Thanks again for your time. Cristian


-- 
Cristian Degli Esposti Boschi
CNR-IMM, Sezione di Bologna,
via Gobetti, 101, 40129, Bologna, Italia
tel. ++39 051 6399152, fax ++39 051 6399216
email: degliesposti -AT- bo.imm.cnr.it
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