[Pw_forum] PP generation with ld1.x (transition metals with semicore states)

Andrea Dal Corso dalcorso at sissa.it
Fri Mar 4 08:56:08 CET 2011


Did you try the Hf PP in pslibrary? 

http://qe-forge.org/projects/pslibrary/

These are still untested PPs, and it would be useful to have feedback
from the users.

Andrea

On Thu, 2011-03-03 at 18:18 -0500, Joe wrote:
> Hello everyone,
> 
> Using ld1.x, I am trying to generate pseudopotentials for elements such 
> as Hf, both scalar relativistic and fully relativistic.  I have followed 
> from the examples given in atomic_doc, and have been making ample use of 
> Paolo Giannozzi's July 9th 2010 tutorial, "Notes on pseudopotential 
> generation" (which is the version with full worked examples for Ti).  
> The information provided by this arsenal as been sufficient to generate 
> and test new USPP/NCPP for Si, C, N, O, and S, as well as "naive" USPP 
> for Hf.  Several of the issues I am reporting below have been mentioned 
> within the pw_forum, and when applicable, I have tried (often with 
> success) the prescriptions offered.
> 
> First, let me share what I have "working".  Below is the input file for 
> a scalar relativistic USPP for Hf that does not contain semicore 
> states.  I have tested it for bulk hafnia and it reproduces published 
> band structure data at fixed cell parameters and fixed atomic 
> coordinates, but gives optimized structures at variance with those 
> (using PBE-based PP) reported in the literature (for example, following 
> from the review given in the 2008 NJP paper by Beltran, Munoz, and 
> Hafner - NJP 10 063031); it agrees most closely with the NCPP PBE 
> structures generated by Zhao and Vanderbilt in PRB 65 233106, except for 
> the angle \beta, which is similar to that reported in PRB 65 174117.  
> The basic summary is that the cell volume is larger than anything published.
> 
> &input
>      title='Hf',
>      zed=72,
>      rel=1,
>      iswitch=3,
>      config='[Xe] 4f14.0 5d2.0 6s2.0 6p0.0',
>      dft='PBE',
>   /
> &inputp
>     lloc=0,
>     pseudotype=3,
>     file_pseudopw='Hf.srl-pbe-rrkjus.UPF',
>     nlcc=.true.,
>     rcore=0.9,
>     author='test',
>     rho0=0.0001,
>   /
> 4
> 6P  2  1  0.00  0.00  2.70  2.70  1
> 5D  3  2  2.00  0.00  1.90  2.30  1
> 5D  3  2  0.00 -0.18  1.90  2.30  1
> 6S  1  0  2.00  0.00  2.50  2.50  1
>   /
> &test
>      nconf=5
>      file_pseudo='Hf.srl-pbe-rrkjus.UPF'
>      ecutmin=20.0, ecutmax=50.0, decut=10.0
>      configts(1)='5d2.0 6s2.0 6p0.0'
>      configts(2)='5d1.0 6s2.0 6p0.0'
>      configts(3)='5d1.0 6s1.0 6p0.0'
>      configts(4)='5d0.0 6s1.0 6p0.0'
>      configts(5)='5d0.0 6s0.0 6p0.0'
>   /
> 
> Note that the test results for different charged (d-depleted) states of 
> Hf are pretty bad.  For those interested in using this as a starting 
> point, an analogous fully relativistic USPP can be generated using the 
> input file:
> 
> &input
>      title='Hf',
>      zed=72,
>      rel=2,
>      iswitch=3,
>      config='[Xe] 4f14.0 5d2.0 6s2.0 6p0.0',
>      dft='PBE',
> /
> &inputp
>     lloc=0,
>     pseudotype=3,
>     file_pseudopw='Hf.rel-pbe-rrkjus.UPF',
>     nlcc=.true.,
>     rcore=0.9,
>     author='test',
>   /
> 7
> 6P  2  1  0.00  0.00  2.70  2.70  0.5
> 6P  2  1  0.00  0.00  2.70  2.70  1.5
> 5D  3  2  2.00  0.00  1.90  2.30  1.5
> 5D  3  2  0.00 -0.18  1.90  2.30  1.5
> 5D  3  2  0.00  0.00  1.90  2.30  2.5
> 5D  3  2  0.00 -0.18  1.90  2.30  2.5
> 6S  1  0  2.00  0.00  2.50  2.50  0.5
>   /
> &test
>      nconf=3
>      file_pseudo='Hf.rel-pbe-rrkjus.UPF'
>      ecutmin=20.0, ecutmax=80.0, decut=10.0
>      configts(1)='5d2.0 6s2.0'
>      configts(2)='5d2.0 6s1.0 6p1.0'
>      configts(3)='5d1.0 6s2.0 6p0.0'
>   /
> 
> The structural discrepancies persist for different oxygen USPP, 
> different optimization procedures, and different sets of parameters 
> (charge density cutoffs, convergence criteria, etc.).
> 
> I am now trying to check if the structural properties can be improved by 
> the inclusion of semicore states, and am starting with the "simplest" 
> case, that of a scalar relativistic NCPP with explicit inclusion of 5S 
> and 5P.  After starting with the fewest number of projectors (one each 
> for 5S, 5P, and 5D), and running into all kinds of problems (anyone who 
> runs ld1.x knows about the kinds of mysterious errors that are 
> generated, and the equally mysterious modifications which result in said 
> errors disappearing), I searched the pw_forum and found the following 
> thread:
> 
> http://www.democritos.it/pipermail/pw_forum/2009-July/013453.html
> 
> Following from this (and making the implicit corrections to the provided 
> files in order to render them processable, such as modifying the 2nd 
> column in the definition of the projectors), I have been working off of 
> the following NCPP input file,
> 
> &input
>      title='Hf',
>      zed=72,
>      rel=1,
>      iswitch=3,
>      config='[Xe] 4f14 5d2 6s2 6p0',
>      dft='PBE',
>   /
> &inputp
>     lloc=0,
>     pseudotype=2,
>     file_pseudopw='Hf.semicore.srl-pbe-rrkjus.UPF',
>     nlcc=.f.,
>     author='test',
>     rho0=0.01,
>   /
> 5
> 5P  2  1  6.00  0.00  1.50  1.50  1
> 5P  2  1  0.00 -1.00  1.50  1.50  1
> 5D  3  2  2.00  0.00  1.90  1.90  1
> 5D  3  2  0.00 -0.20  1.90  1.90  1
> 5S  1  0  2.00  0.00  1.20  1.20  1
>   /
> &test
>      nconf=1
>      file_pseudo='Hf.semicore.srl-pbe-rrkjus.UPF'
>      ecutmin=20.0, ecutmax=50.0, decut=10.0
>      configts(1)='5s2 5p6 5d2 6s2 6p0',
>   /
> 
> and have been varying the energy for the empty 5P projector, changing 
> lloc (and rcloc when applicable), toying with rho0, and fiddling with 
> the cutoffs, to no avail.  The latest error is the not-so-helpful:
> 
>   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>       from run_pseudo : error #         1
>       Errors in PS-KS equation
>   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> 
> Changing parameters merely changes the error, it seems.  I know this is 
> a highly-specific cooking problem, but if anyone has any suggestions on 
> how to proceed, I would be extremely grateful.  With some help, 
> hopefully I can generate a good, tested set of USPPs for Hf and fill in 
> that blank on PWSCF's pseudopotential page!
> 
> Joseph Turnbull
> NC State University
> 
> 
> 
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
-- 
Andrea Dal Corso                    Tel. 0039-040-3787428
SISSA, Via Bonomea 265              Fax. 0039-040-3787249
I-34136 Trieste (Italy)             e-mail: dalcorso at sissa.it





More information about the users mailing list