<div dir="ltr">Yes....and no.<div><br></div><div>In 14.2 Peter added a "Push" for the 1st iteration if :DIS is small, some lines starting with</div><div><div>#check :dis of first cycle and rerun mixer with increased mixing</div></div><div>after the execution of mixer</div><div><br></div><div>This was added to avoid stagnation where it just takes a few small steps and stops.</div><div><br></div><div>In your case this "disturbed" 14.2 and it is adjusting the greed down to try and stabilize. In 13.1 this push is missing, so it starts with a small greed and finds what it thinks might be a solution.</div><div><br></div><div>The next version does not have this push (it is done inside mixer), but still needs work.</div><div><br></div><div>Unfortunately both cases are really bad -- :FCheck should be close to 1.0 or less, and your values indicate something really wrong. For reasons I don't understand MSR1a does not behave well with non-centro symmetric structures. I don't know why this is.</div><div><br></div><div>N.B., MSR1a is not perfect, and there are cases where it does not want to behave well. Whenever the model is susceptible to ghostbands it is not ideal. I am currently trying a few things, but.....</div><div><br></div><div>N.N.B., Peter's explanation of why :FCHECK can be large is that the linearization of different atoms is unbalanced. Maybe he has ideas about how to cure this, it is beyond me.</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Nov 30, 2015 at 9:00 AM, Elias Assmann <span dir="ltr"><<a href="mailto:elias.assmann@gmail.com" target="_blank">elias.assmann@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi List,<br>
<br>
I reply to this thread<br>
<<a href="http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg13276.html" rel="noreferrer" target="_blank">http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg13276.html</a>>.<br>
This is still about the same set of oxide calculations.<br>
<br>
Laurence Marks alerted me that :FCHECK (sum of forces) was large (see<br>
below). This is the same over a set of similar calculations (somewhat<br>
different structures, GGA+U vs. plain GGA), and does not seem to get<br>
better even after hundreds of calculations.<br>
<br>
I have been using the latest Wien2k (14.2), but I did similar things<br>
before with 13.1 and I did not remember having this problem, at least<br>
to this extent. So I compiled 13.1 (same options as 14.2) and<br>
switched one of my calculations to it for 10 iterations.<br>
<br>
Indeed, it seems that 13.1 is more “well-behaved†in this case than<br>
14.2 — in any case they are different. Below, I include some output<br>
of the two versions, starting from the same charge density in both<br>
cases.<br>
<br>
As you can see, the two versions are the more or less the same in the<br>
first iteration, but diverge from there; and 13.1 seems to converge,<br>
in contrast to 14.2. Also, 13.1 seems to be already satisfied with<br>
the structure (it switches MSR1a off), while 14.2 continues<br>
minimizing. The greed (on whose smallness Prof. Marks also commented)<br>
is pretty similar.<br>
<br>
To me, that suggests that I should go on with these calculations using<br>
the older Wien. Is there any reason that doing so might be “unsafe�<br>
<br>
<br>
    Elias<br>
<br>
<br>
14.2 :FCHECK:Â Â Â 11.008001043Â Â 12.164812176Â Â -14.416571844<br>
   :FCHECK:  249.814119002  264.664202568 -694.164686632<br>
   :FCHECK:   97.292437031  103.207655853 -256.561081883<br>
   :FCHECK:  126.184534662  136.666423509  -39.224005265<br>
   :FCHECK:  176.349427337  188.815368048  36.914398561<br>
   :FCHECK:   50.400659984  67.046955772  76.978472788<br>
   :FCHECK:  -74.640170442  25.157628216  121.498217602<br>
   :FCHECK:  -82.337983720  28.388321933  121.952351989<br>
   :FCHECK:  -130.382154150  24.859863620  204.399962720<br>
   :FCHECK:  -39.381668995  -31.379111345  91.507308943<br>
<br>
13.1 :FCHECK:Â Â Â 11.009473749Â Â 12.153718710Â Â -14.482142314<br>
   :FCHECK:   10.707248409  11.500977675  -16.514184574<br>
   :FCHECK:   10.289877753  10.742969135  -10.026151044<br>
   :FCHECK:   7.566779454   6.128096382  -3.725471547<br>
   :FCHECK:   3.572302068   1.087140350   6.011501945<br>
   :FCHECK:   -4.275691705  -7.052038873  31.588782325<br>
   :FCHECK:   -6.385420320  -8.403344519  33.874614737<br>
   :FCHECK:   -6.106651082  -8.096761064  35.566398852<br>
   :FCHECK:   -5.627436387  -7.565248768  32.843232377<br>
   :FCHECK:   -3.074299958  -4.674255384  27.987425362<br>
<br>
14.2 :ENEÂ : *WARNING** TOTAL ENERGYÂ Â Â -222784.46215529<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46926026<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46462435<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46263442<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46223935<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46214440<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46218336<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46213858<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46236760<br>
   :ENE : *WARNING** TOTAL ENERGY   -222784.46181283<br>
<br>
13.1 :ENEÂ : ********** TOTAL ENERGYÂ Â Â -222784.46212826<br>
   :ENE : ********** TOTAL ENERGY   -222784.46212374<br>
   :ENE : ********** TOTAL ENERGY   -222784.46212843<br>
   :ENE : ********** TOTAL ENERGY   -222784.46207306<br>
   :ENE : ********** TOTAL ENERGY   -222784.46209495<br>
   :ENE : ********** TOTAL ENERGY   -222784.46204241<br>
   :ENE : ********** TOTAL ENERGY   -222784.46199458<br>
   :ENE : ********** TOTAL ENERGY   -222784.46200681<br>
   :ENE : ********** TOTAL ENERGY   -222784.46200118<br>
   :ENE : ********** TOTAL ENERGY   -222784.46201120<br>
<br>
(It appears that the warnings come from the forces. As mentioned<br>
before there is not :WAR tag.)<br>
<br>
14.2 :DIS : ( 0.0048283 for atom  7 spin 1)   0.0015628<br>
   :DIS : ( 0.1175699 for atom  5 spin 1)   0.0137938<br>
   :DIS : ( 0.0692919 for atom  5 spin 1)   0.0083222<br>
   :DIS : ( 0.0098508 for atom  7 spin 1)   0.0017036<br>
   :DIS : ( 0.0167530 for atom  5 spin 1)   0.0022822<br>
   :DIS : ( 0.0278296 for atom  7 spin 1)   0.0038446<br>
   :DIS : ( 0.0366785 for atom  5 spin 1)   0.0048138<br>
   :DIS : ( 0.0371346 for atom  5 spin 1)   0.0047958<br>
   :DIS : ( 0.0559135 for atom  5 spin 1)   0.0068198<br>
   :DIS : ( 0.0157960 for atom  5 spin 1)   0.0035943<br>
<br>
13.1 :DIS : ( 0.0048362 for atom  7 spin 1)   0.0015593<br>
   :DIS : ( 0.0022134 for atom  12 spin 2)   0.0012247<br>
   :DIS : ( 0.0052633 for atom  5 spin 1)   0.0014252<br>
   :DIS : ( 0.0015732 for atom  5 spin 1)   0.0007705<br>
   :DIS : ( 0.0046946 for atom  7 spin 1)   0.0010640<br>
   :DIS : ( 0.0018880 for atom  8 spin 2)   0.0011590<br>
   :DIS : ( 0.0017283 for atom  5 spin 1)   0.0008169<br>
   :DIS : ( 0.0009736 for atom  8 spin 2)   0.0006944<br>
   :DIS : ( 0.0018888 for atom  5 spin 1)   0.0007013<br>
   :DIS : ( 0.0009991 for atom  7 spin 1)   0.0003925<br>
<br>
14.2 :MIXÂ :Â Â PRATTÂ REG: 1.00E-06Â GREED: 0.200<br>
   :MIX :  PRATT REG: 1.00E-06 GREED: 0.200 Reduce 0.25 0.20<br>
   :MIX :  MSE1a REG: 1.88E-06 GREED: 0.120 Newton 1.00 0.01<br>
   :MIX :  MSE1a REG: 2.17E-06 GREED: 0.083 Newton 1.00 0.01<br>
   :MIX :  MSE1a REG: 3.19E-06 GREED: 0.050 Newton 1.00 0.01<br>
   :MIX :  MSE1a REG: 4.08E-06 GREED: 0.034 Newton 1.00 0.03<br>
   :MIX :  MSE1a REG: 5.17E-06 GREED: 0.022 Newton 1.00 0.00<br>
   :MIX :  MSE1a REG: 5.20E-06 GREED: 0.021 Newton 1.00 0.06<br>
   :MIX :  MSE1a REG: 7.51E-06 GREED: 0.018 Newton 1.00 0.14<br>
   :MIX :  MSE1a REG: 4.52E-06 GREED: 0.017 Newton 1.00 0.10<br>
<br>
13.1 :MIXÂ :Â Â PRATTÂ REG: 1.00E-06Â GREED: 0.025<br>
   :MIX :  MSR1a REG: 1.00E-06 GREED: 0.030 Newton 1.00 0.03<br>
   :MIX :  MSE1a REG: 1.59E-06 GREED: 0.030 Newton 1.00 0.18<br>
   :MIX :  MSE1a REG: 2.61E-06 GREED: 0.042 Newton 1.00 0.29<br>
   :MIX :  MSE1a REG: 3.72E-06 GREED: 0.057 Newton 1.00 0.54<br>
   :MIX :  MSE1a REG: 3.58E-06 GREED: 0.093 Newton 1.00 0.46<br>
   :MIX :  PRATT REG: 1.00E-06 GREED: 0.025<br>
   :MIX :  MSR1  REG: 1.00E-06 GREED: 0.050 Newton 1.00 0.05<br>
   :MIX :  MSE1  REG: 1.60E-06 GREED: 0.050 Newton 1.00 0.22<br>
   :MIX :  MSE1  REG: 2.41E-06 GREED: 0.055 Newton 1.00 0.40<br>
<br>
On 11/03/2015 02:47 PM, Laurence Marks wrote:<br>
> I am not sure exactly what the problem(s) were, but from you case.scf it<br>
> was "right" that there were Warnings<br>
><br>
> a) :FCHECK (bottom of case.scf) was large. This is the sum of all the<br>
> forces, and should be small. Particularly for cells without inversion<br>
> one can get bad, highly asymmetric densities in which case MSR1a can<br>
> have problems.<br>
><br>
> b) The greed is small. Too small a value can be as bad as too large. I<br>
> have struggled with this for years and failed to find a strong ansatz<br>
> for this, although I believe the next release of the mixer will be better.<br>
<span class="HOEnZb"><font color="#888888"><br>
<br>
<br>
--<br>
Elias Assmann<br>
Institute of Theoretical and Computational Physics<br>
TU Graz          ⟨<a href="https://itp.tugraz.at/" rel="noreferrer" target="_blank">https://itp.tugraz.at/</a>⟩<br>
<br>
<br>
</font></span></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Professor Laurence Marks<br>Department of Materials Science and Engineering<br>Northwestern University<br><a href="http://www.numis.northwestern.edu" target="_blank">www.numis.northwestern.edu</a><div>Corrosion in 4D: <a href="http://MURI4D.numis.northwestern.edu" target="_blank">MURI4D.numis.northwestern.edu</a><br>Co-Editor, Acta Cryst A<br>"Research is to see what everybody else has seen, and to think what nobody else has thought"<br>Albert Szent-Gyorgi</div></div></div>
</div>