[Pw_forum] C pseudo regeneration

[Dal Corso Andrea]

On Mon, 2007-08-27 at 15:16 +0300, Hande Ustunel wrote:
> Dear forum members,
> 
> I have a problem concerning the reproduction of one of the C
> pseudopotentials. I'm trying to reproduce the C.pz-rrkjus.UPF
> pseudopotential as best I can using the input provided below. Although I
> get excellent agreement with the log derivatives and test cases (pls see
> below), even with cutoffs of 40/400 Ryd, I get a diamond lattice constant
> that is 1.2% too little and a rather bumpy E vs a curve. I've tried a
> rather exhaustive set of different parameters but I haven't been able to
> generate a smooth enough curve. The C.pz-rrkjus.UPF from the web site on
> the other hand gives a very nice smooth curve with an error of only 0.9%
> for the same calculation parameters. I've posted both curves here.
> 
>     http://www.physics.metu.edu.tr/~hande/curves
> 
> I guess the errors are not terribly different but should I be worried about
> the bumpiness? If yes, it would be really helpful if anyone could spot the
> difference between my input and the pseudo online. If not, any suggestion
> on improving my pseudo would be more than welcome. Thank you very much in
> advance. 
> 
> Best regards,
> Hande
> 
> PS : I'm using version 3.2.
> 
> Input :
> -------
> 
> &input
>      atom='C',
>      rlderiv=3.0,
>      eminld=-4.0,
>      emaxld= 4.0,
>      deld  = 0.02,
>      nld   = 3,
>      config=' 1s2 2s2 2p2 3d0.00',
>      iswitch=3,
>      prefix='c'
>      dft='pz',
>  /
>  &inputp
>    pseudotype=3,
>    lloc=2,
>    tm=.false.,
>    nlcc=.false.,
>    file_pseudopw='C.pz.uspp-rrkj.UPF',
>  /
> 5
> 2S  1  0   2     0.00  1.3 1.6
> 2S  1  0    0     -0.4  1.3 1.6
> 2P  2  1   2     0.00  1.6 1.6
> 2P  2  1    0     -0.1  1.6 1.6

The core radii of the 2P wavefunctions seem strange to me. This is a
norm conserving pseudopotential for the 2P functions. 1.3 1.6 usually
work.

Andrea


> 3D  3  2   -2.0   2.00   1.3    1.3
>  &test
>    nconf=1,
>    configts(1)='2s2 2p2 ',
>  /
> 
> 
> 
> Test results :
> --------------
> Atomic configuration : s2 p2
>      n l     nl             e AE (Ry)        e PS (Ry)    De AE-PS (Ry)
>      1 0     2S   1( 2.00)       -1.00195       -1.00210        0.00015
>      2 1     2P   1( 2.00)       -0.39860       -0.39861        0.00002
> 
> Test case 1 : s2 p1.75
>      n l     nl             e AE (Ry)        e PS (Ry)    De AE-PS (Ry)
>      1 0     2S   1( 2.00)       -1.20025       -1.20038        0.00012
>      2 1     2P   1( 1.75)       -0.58967       -0.58941       -0.00026
> 
> Test case 2 : s1.00 p1.50
>      n l     nl             e AE (Ry)        e PS (Ry)    De AE-PS (Ry)
>      1 0     2S   1( 1.00)       -2.38716       -2.38539       -0.00178
>      2 1     2P   1( 1.50)       -1.76433       -1.76042       -0.00391
> 
> Test case 3 : s1.00 p1.50
>      n l     nl             e AE (Ry)        e PS (Ry)    De AE-PS (Ry)
>      1 0     2S   1( 1.00)       -2.38716       -2.38539       -0.00178
>      2 1     2P   1( 1.50)       -1.76433       -1.76042       -0.00391
> 
> 
> 
-- 
Andrea Dal Corso                    Tel. 0039-040-3787428
SISSA, Via Beirut 2/4               Fax. 0039-040-3787528
34014 Trieste (Italy)               e-mail: dalcorso at sissa.it