[Pw_forum] Using a pseudopotential with ghosts

[Pietro Bonfa']

Dear QuantumEspresso users,

I produced a NC and a US pseudopotential for Y since I obtained negative
rho warnings (even with large cutoffs for rho) with the pseudopotential
from the QE web-page.

The NC provides good results but cutoffs are far to high for my calculation.

The US pseudopotetial works perfectly for all the configurations I
tested except for the one with an additional electron i.e. 4s2 4p6 4d2.0
5s2.0 (the pseudo has semicore s and p in valence) where ghosts appear.

The logarithmic derivative looks good enough in the energy range ± 8
Ry but a (ghost?) spike appear for ~9 Ry in the p channel where the all
electron log derivative is almost flat.

I also checked the band structure of hexagonal Y obtained with the US
pseudopotential against FP-LAPW result and they perfectly match.

So the point is: as long as the pseudopotential is not used in 4d2.0
5s2.0 configuration, is it safe to use it?

Thanks in advances,
kind regards,
Pietro Bonfa'
PhD student, University of Parma,
Italy
-------------- next part --------------
 &input
   title='Y',
   prefix='Y/ld1'
   zed=39.,
   rel=1,
   config='[Kr] 4d1.5 5s1.5 5p0.0',
   iswitch=3,
   dft='PBE'
   nld=3, ! s, p, d ...
        eminld=-10,
        emaxld=10,
        deld=0.01d0,
        rlderiv=2.0,
 /
 &inputp
   pseudotype=3,
   file_pseudopw='Y.pbe-nsp-rrkjus.UPF',
   author='PB',
   lloc=-1,
   rcloc=1.4,
   which_augfun='PSQ',
   rmatch_augfun_nc=.true.,
   nlcc=.true.,
   tm=.true.
   !rcore=0.8,
 /
6
4S  1  0  2.00  0.00  0.95  1.30  0.0
5S  2  0  1.50  0.00  0.95  1.30  0.0
4P  2  1  6.00  0.00  0.95  1.70  0.0
5P  3  1  0.00  0.00  0.95  1.70  0.0
4D  3  2  1.50  0.00  0.95  1.70  0.0
4D  3  2 -2.00  0.30  0.95  1.70  0.0