Thank you for your help. That would be much appreciated ---------------------------------------------------------------------------------------------------------------- Joshua D. Davis
Graduate Assistant Department of Chemistry Michigan State University 578 S. Shaw Lane, room 432 East Lansing, MI 48824 ----------------------------------------------------------------------------------------------------------------- On Tue, Sep 23, 2014 at 1:05 PM, Joshua Davis <davis.d.josh at gmail.com> wrote: > Thank you for your help. That would be much appreciated > > > ---------------------------------------------------------------------------------------------------------------- > Joshua D. Davis > > Graduate Assistant > Department of Chemistry > Michigan State University > > 578 S. Shaw Lane, room 432 > East Lansing, MI 48824 > > ----------------------------------------------------------------------------------------------------------------- > > On Fri, Sep 19, 2014 at 4:59 PM, Holzwarth, Natalie <natalie at wfu.edu> > wrote: > >> Dear Joshua, >> If you send me the full input file I will be glad to test the PAW >> datasets constructed with ATOMPAW code. THe functions on our webpage >> http://pwpaw.wfu.edu are mostly focused on accuracy in comparison with >> the all-electron results and may not rapidly converge with ecut. However, >> there are several other efforts to generate PAW functions that may converge >> more rapidly.... Sincerely, Natalie Holzwarth >> >> >> N. A. W. Holzwarth email: >> natalie at wfu.edu >> Department of Physics web: >> http://www.wfu.edu/~natalie >> Wake Forest University phone: >> 1-336-758-5510 >> Winston-Salem, NC 27109 USA office: Rm. 300 Olin >> Physical Lab >> >> On Fri, Sep 19, 2014 at 4:16 PM, Joshua Davis <davis101 at chemistry.msu.edu >> > wrote: >> >>> The plot of the convergence does look like it is oscillating and sort of >>> converging to a point but at fairly large energy cut-off. These potentials >>> were off the "ready to use" potentials on the QE website. Would you have >>> confidence in the potentials? PAW is the newest method and there are not >>> many of them. They all use have scalar relativity and not fully >>> relativity. I figured that would be good enough. >>> >>> Thanks >>> >>> >>> >>> ---------------------------------------------------------------------------------------------------------------- >>> Joshua D. Davis >>> >>> Graduate Assistant >>> Department of Chemistry >>> Michigan State University >>> >>> 578 S. Shaw Lane, room 432 >>> East Lansing, MI 48824 >>> >>> ----------------------------------------------------------------------------------------------------------------- >>> >>> On Fri, Sep 19, 2014 at 3:43 PM, Paolo Giannozzi < >>> paolo.giannozzi at uniud.it> wrote: >>> >>>> Maybe the nonlinear core correction is slowly converging, >>>> especially in Sodium which has s and p semicore electrons >>>> and a very localized (pseudo-)core charge. Just guessing. >>>> >>>> P. >>>> >>>> On Fri, 2014-09-19 at 14:20 -0400, Joshua Davis wrote: >>>> > I was performing a convergence test for the energy cut-off for the >>>> > density for a set of PAW potentials just to make sure, but I have some >>>> > results that confuse me a bit. >>>> > >>>> > >>>> > The compound is a NaB5C (space group: Pm-3m) so the potentials I used >>>> > were: >>>> > >>>> > B.pbe-n-kjpaw_psl.0.1.UPF >>>> > C.pbe-n-kjpaw_psl.0.1.UPF >>>> > Na.pbe-spn-kjpaw_psl.0.2.UPF >>>> > >>>> > >>>> > The cell was also completely relaxed each time with cell and ion >>>> > dynamic being "bfgs" algorithm >>>> > >>>> > >>>> > >>>> > Already did a ecutwfc and kpoint convergence test for each and I found >>>> > and ecutwfc of 35 Ry and a kpoint mesh of 4x8x8 to be sufficient (I am >>>> > calculating a cell doubled in one direction). >>>> > >>>> > >>>> > When I did the ecutwfc convergence test I went from 10 to 50 Ry in >>>> > increments of 5 Ry, and I kept the default ecutrho=4*ecutwfc for each >>>> > run. >>>> > >>>> > >>>> > so when I did the ecutrho convergence kept ecutwfc at 35 Ry and the >>>> > kpoints at 4x8x8 and started at 140 and went to 400 Ry. >>>> > >>>> > >>>> > The graph of my convergence is shown below: >>>> > Inline image 1 >>>> > >>>> > >>>> > and if the fourm scrubs the image here is the raw data: >>>> > ecutrho(Ry),TotalEnergy(ry) >>>> > 140,-370.0979858 >>>> > 150,-370.0980023 >>>> > 160,-370.0995505 >>>> > 170,-370.1019804 >>>> > 180,-370.1047998 >>>> > 190,-370.1072663 >>>> > 200,-370.1086284 >>>> > 250,-370.1048218 >>>> > 300,-370.1049835 >>>> > 400,-370.1060986 >>>> > >>>> > >>>> > >>>> > >>>> > The convergence shows a density cut-off of 140 Ry and 150 Ry to be >>>> > pretty similar in calculated energy, but after that the calculated >>>> > energy quickly drops until a cut-off of 200 Ry. After that the >>>> > calculated energy shoots up at a cut-off of 250 Ry by 0.004 then >>>> > tappers down by 0.002 Ry as it gets to a cut-off of 400 Ry. >>>> > >>>> > >>>> > I thought the energy cut-off for density would be the easiest after >>>> > ecutwfc and kpoint, but I want to make sure my results would be fine >>>> > based on what I read for he input documentation for ecutrho. It says >>>> > ecutrho=4*ecutwfc is usually good (which is pretty standard for the >>>> > PAW method), but I wanted to make sure. I thought the calculated >>>> > energy would not have changed or the calculated energy would have >>>> > converged at a reasonable value. >>>> > >>>> > >>>> > Am I doing something wrong? Is the ratio of ecutwfc and ecutrho too >>>> > off at the higher energy ecutrho cut-off? Other posts suggest >>>> > lowering ecutwfc and keeping ecutrho cut-off constant for proper >>>> > convergence, should I have done this? I figured sneaking up ecutrho >>>> > would be okay. Am I dumb and this is just an artifact of the PAW >>>> > method at a large ratio of ecutwfc to ecutrho? Is this an artifact of >>>> > how the FFT mesh is implemented in QE 5.1? Should I have not gone >>>> > that high in my density cut-off? >>>> > >>>> > >>>> > Any help would be much appreciated. >>>> > >>>> > >>>> > Other considerations: >>>> > I used QE 5.1 compiled with ifort 13 and mkl 11. >>>> > >>>> > >>>> > &CONTROL >>>> > calculation = 'vc-relax', >>>> > etot_conv_thr = 1.0D-5, >>>> > forc_conv_thr = 1.0D-4 >>>> > / >>>> > >>>> > >>>> > &SYSTEM >>>> > ibrav = 0, >>>> > nat = 14, >>>> > ntyp = 3, >>>> > nosym = .TRUE., >>>> > nspin = 1, >>>> > occupations = 'fixed', >>>> > >>>> > >>>> ---------------------------------------------------------------------------------------------------------------- >>>> > Joshua D. Davis >>>> > >>>> > Graduate Assistant >>>> > Department of Chemistry >>>> > Michigan State University >>>> > 578 S. Shaw Lane, room 432 >>>> > >>>> > >>>> > East Lansing, MI 48824 >>>> > >>>> > >>>> ----------------------------------------------------------------------------------------------------------------- >>>> > >>>> > _______________________________________________ >>>> > Pw_forum mailing list >>>> > Pw_forum at pwscf.org >>>> > http://pwscf.org/mailman/listinfo/pw_forum >>>> >>>> >>>> _______________________________________________ >>>> Pw_forum mailing list >>>> Pw_forum at pwscf.org >>>> http://pwscf.org/mailman/listinfo/pw_forum >>>> >>> >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> Pw_forum at pwscf.org >>> http://pwscf.org/mailman/listinfo/pw_forum >>> >> >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum >> > > -------------- next part -------------- An HTML attachment was scrubbed... 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