[Pw_forum] generating pseudopotential problem

[Gabriele Sclauzero]

I've not much experience in producing PP, but I recognize some problems in your input 
file. I can point them out, while you wait for a more definitive reply...

premlata pandit wrote:
> Dear  Pwscf User
>  We have generated ultrasoft pseudopotential for Pm by using following 
> configuration
>        4F     4     3     5.00    0.00     2.10    2.10    2.50
>        4F     4     3     0.00   -0.10     2.10    2.10    3.50

These two rows look strange to me. If you want to generate US PP, you need at least 2 
energies for each channels and specify the 2nd cutoff radius bigger than the first. They 
are the same for the channels you want pseudize within the norm-conserving recipe.
I don't understand if your input above is for US with rel=1 or for NC with rel=2.
In the relativistic case (rel=2), for each l, the number of projectors doubles (you have 
one with j=l+1/2 and another with j=l-1/2, where j is the number you specify in the last 
column).
So, your input for relativistic USPP should look more like:

         4F     4     3     5.00    0.00     2.10    2.40    2.50
         4F     4     3     0.00   -0.10     2.10    2.40    2.50
         4F     4     3     0.00    0.00     2.10    2.40    3.50
         4F     4     3     0.00   -0.10     2.10    2.40    3.50

Of course this is not sufficient to get a relativistic US-PP, you need to play a lot with 
cut-off radius and energies as well as maybe adding p or d projectors... it is usually a 
difficult task to obtain a working PP for rare earth elements.

>        6S     1     0     2.00    0.00     2.40    2.40    0.50
> 
>   By using above configuration, we have got output. 

This does not mean that the PP will work correctly elsewhere than the atom in the 
configuration used for generating the PP...

My suggestion is to look at the input files for PP generation in 
espresso/atomic_doc/pseudo_library/LDA/REL/ and understand what you need to specify.

Regards

GS



>But when we used 
> split 4F configuration ( i.e. more than 2 ), we found some error.
>  The input file Pm2.in, which is used to generated pp, is also attached 
> with this mail.
>  There are some question -
>  1. is input file and generated pseudopotential is correct?
>  2. Why we did not get results, when we used split 4F configuration ?
>    anyone can help me , i would be greatful.
>  
> Premlata Pandit
> Ph.d. student,
> Barkatullah university,
> Bhopal 462026,
> MP, India
> 
> 
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| Gabriele Sclauzero, PhD Student                  |
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