[Pw_forum] compatibility between pseudopotential choice and input_dft token

[Cristian Degli Esposti Boschi]

 > it means that what is specified as "input_dft" is used, what is
 > written in the pseudopotential files is discarded.

 > P.

Thanks again for the answers related to the choice of van der waals
density functionals by means of the input_dft variable for pw.x

To be precise, I guess that what is written in the pseudopotential
file is discarded only as long as the form of the exchange-correlation
functional is concerned. I mean, what is actually written in the
pseudopotential file for a specific atomic element is of course
used to build the ionic interactions (including core electrons).

For example, I tested two different available pseudopotential files
for carbon, namely C.pbe-mt_fhi.UPF and C.pz-vbc.UPF
(both norm-conserving but built with different xc models, I guess...)
and the rest of the input file being identical, including 
input_dft="vdw-df", and the resulting output are of course different
meaning that something read from the UPF files makes the difference.
So, input_dft="vdw-df" overrides the specification of the xc functional
by imposing "sla+pw+rpb+vdw1" in both cases but at some point
the two different files will show up differences due to the fact
that they were built using different xc schemes; am I right? If so, 
sorry for the somehow silly question and thanks again.

Cristian


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Cristian Degli Esposti Boschi
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