nwpw optimization wrong
Gets Around
3:22:21 AM PST - Sat, Nov 10th 2012
I am having multiple problems optimizing geometry in nwpw at gamma point. My unit cell collapses and atoms become coordinated in an unreasonable fashion. Also, it's taking forever (now already 100 cycles) to optimize and it's still far away from being over. Also, I am getting bunch of strange warnings, such as 

Error reading psi - bad unitcell

 - Ignored if the following  parameter is set

 - set nwpw:psi_nolattice .true.

and, usual, pseudopotential incorrectly formatted. What a mess...

It's probably mostly since I am familiar with other periodic boundary condition codes, not NWChem, but logically it shouldn't collapse the unit cell and shouldn't take 100 cycles to optimize crystal taken from the experimental coordinates.

I uploaded two files to the links below, would appreciate any guidance

Jonas

[1]
[2]

Gets Around
5:17:40 AM PST - Sun, Nov 11th 2012
both optimizations simply ran out of 400 cycles

Gets Around
1:12:50 PM PST - Mon, Nov 12th 2012
The problem is that you're using SIC with the wrong type of optimizer. You can see the problem in your first iteration.

       ============ Grassmann lmbfgs iteration ============
    >>>  ITERATION STARTED AT Fri Nov  9 16:31:36 2012  <<<

   iter.           Energy         DeltaE       DeltaRho 

   ------------------------------------------------------

    -  15 steepest descent iterations performed

     10   -0.2933164569E+03   -0.28251E+01    0.25142E+02

    -  10 steepest descent iterations performed

     20   -0.3044814762E+03   -0.38190E+00    0.37921E+00

    -  10 steepest descent iterations performed

     30   -0.3069735714E+03   -0.12021E+00    0.13592E+00

    -  10 steepest descent iterations performed

     40   -0.3079887118E+03   -0.37873E-01    0.35121E-01

    -  10 steepest descent iterations performed

     50   -0.3083151316E+03   -0.94546E-02    0.14078E-01

     60   -0.3083580553E+03    0.56843E-13    0.14995E-01

 *** energy going up. iteration not terminated

    -  10 steepest descent iterations performed

     70   -0.3086062132E+03    0.00000E+00    0.53551E-02

     80   -0.3086062132E+03    0.28422E-13    0.11288E-27

 *** energy going up. iteration not terminated

 *** tolerance ok. iteration terminated

    >>>  ITERATION ENDED   AT Fri Nov  9 16:36:53 2012  <<<



My suggestion is to first run it with pbe96 and then turn on SIC. You'll first need to localize the orbitals for an initial guess and set the minimizer to the following

set nwpw:minimizer 4


A strategy would be

nwpw
  xc pbe96
end
task pspw optimize ignore

nwpw
  xc pbe96-0.4SIC
end
set nwpw:minimizer 4
task pspw wannier
task pspw wannier
task pspw optimize ignore

Gets Around
1:34:02 PM PST - Mon, Nov 12th 2012
thank you, I will adjust. Is there any effect of the cutoff (I am using 36 from one of yoru papers) on optimization? I will test cutoff WRT bandgap properties but not sure whether there is effect on the optimization

Gets Around
4:24:43 PM PST - Mon, Nov 12th 2012
Much better. It still runs out of cycles when optimiznig with bpe, though and I am not sure why. WHat I can see is this, as if there is some numerical inaccuracy that makes the optimization simply oscillate near the minimum and it never converges.

Are there tricks to using some tighter settign (large grid?) to finsih this optimization?

 Step       Energy      Delta E   Gmax     Grms     Xrms     Xmax   Walltime

 ---- ---------------- -------- -------- -------- -------- -------- --------
@ 304 -312.94981443 5.8D-05 0.02416 0.00798 0.00514 0.03107 9844.8
                                                                   



Taking step in negative mode    1  eval=-1.1D-02 grad= 8.1D-04 step=-7.2D-02

Restricting overall step due to uphill motion.   alpha=  0.50

Gets Around
12:13:15 AM PST - Tue, Nov 13th 2012
My other structures managed to converge PBE but in PBE-SIC it has difficulties during SCF cycles, what conveger aids should I use to rectify that?

Energy Calculation 



         ======= Stiefel conjugate gradient iteration =======
    >>>  ITERATION STARTED AT Tue Nov 13 00:13:13 2012  <<<

   iter.           Energy         DeltaE       DeltaRho 

   ------------------------------------------------------

     10   -0.3129688105E+03   -0.54783E-03    0.85538E-05

     20   -0.3129729364E+03   -0.56193E-03    0.30289E-04

    -  10 steepest descent iterations performed

     30   -0.3129552999E+03   -0.29230E-05    0.69584E-09

     40   -0.3129553282E+03   -0.27634E-05    0.61649E-09

     50   -0.3129553551E+03   -0.26250E-05    0.54839E-09

     60   -0.3129553806E+03   -0.25040E-05    0.48960E-09

     70   -0.3129554051E+03   -0.23972E-05    0.43857E-09

     80   -0.3129554285E+03   -0.23023E-05    0.39405E-09

     90   -0.3129554511E+03   -0.22173E-05    0.35504E-09

    100   -0.3129554728E+03   -0.21407E-05    0.32072E-09

    110   -0.3129554938E+03   -0.20714E-05    0.29040E-09

    120   -0.3129555142E+03   -0.20082E-05    0.26353E-09

    130   -0.3129555340E+03   -0.19505E-05    0.23963E-09

    140   -0.3129555532E+03   -0.18975E-05    0.21832E-09

    150   -0.3129555719E+03   -0.18487E-05    0.19926E-09

    160   -0.3129555901E+03   -0.18035E-05    0.18218E-09

    170   -0.3129556079E+03   -0.17616E-05    0.16683E-09

    180   -0.3129556253E+03   -0.17226E-05    0.15300E-09

    190   -0.3129556423E+03   -0.16861E-05    0.14052E-09

    200   -0.3129556590E+03   -0.16520E-05    0.12924E-09

    210   -0.3129556754E+03   -0.16200E-05    0.11902E-09

    220   -0.3129556914E+03   -0.15900E-05    0.10974E-09

    230   -0.3129557071E+03   -0.15616E-05    0.10132E-09

    240   -0.3129557226E+03   -0.15348E-05    0.93645E-10

    250   -0.3129557378E+03   -0.15095E-05    0.86653E-10

    260   -0.3129557528E+03   -0.14855E-05    0.80272E-10

    270   -0.3129557675E+03   -0.14627E-05    0.74440E-10

    280   -0.3129557820E+03   -0.14410E-05    0.69105E-10

    290   -0.3129557963E+03   -0.14204E-05    0.64217E-10

    300   -0.3129558104E+03   -0.14007E-05    0.59734E-10

    310   -0.3129558243E+03   -0.13819E-05    0.55619E-10

    320   -0.3129558380E+03   -0.13639E-05    0.51837E-10

    330   -0.3129558516E+03   -0.13466E-05    0.48359E-10

    340   -0.3129558649E+03   -0.13301E-05    0.45156E-10

    350   -0.3129558781E+03   -0.13142E-05    0.42204E-10

    360   -0.3129558912E+03   -0.12989E-05    0.39481E-10

    370   -0.3129559041E+03   -0.12843E-05    0.36967E-10

    380   -0.3129559169E+03   -0.12701E-05    0.34644E-10

    390   -0.3129559295E+03   -0.12565E-05    0.32496E-10

    400   -0.3129559420E+03   -0.12433E-05    0.30508E-10

    410   -0.3129559544E+03   -0.12306E-05    0.28668E-10

    420   -0.3129559666E+03   -0.12183E-05    0.26961E-10

    430   -0.3129559787E+03   -0.12064E-05    0.25379E-10

    440   -0.3129559907E+03   -0.11949E-05    0.23910E-10

    450   -0.3129560026E+03   -0.11838E-05    0.22546E-10

    460   -0.3129560144E+03   -0.11730E-05    0.21277E-10

    470   -0.3129560261E+03   -0.11625E-05    0.20098E-10

    480   -0.3129560376E+03   -0.11523E-05    0.19000E-10

    490   -0.3129560491E+03   -0.11424E-05    0.17978E-10

    500   -0.3129560605E+03   -0.11328E-05    0.17025E-10

    510   -0.3129560717E+03   -0.11235E-05    0.16137E-10

    520   -0.3129560829E+03   -0.11143E-05    0.15308E-10

    530   -0.3129560940E+03   -0.11055E-05    0.14534E-10

    540   -0.3129561050E+03   -0.10968E-05    0.13810E-10

    550   -0.3129561159E+03   -0.10884E-05    0.13134E-10


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