Dear Prof. Blaha, Marks and WIEN2k community,
I finally tried the structure optimization using MSR1a and mBJ
(without SOC).
As I have a previous successful optimization of the structure using
MSEC1 and PBE (min_lapw), I repeated the same parameters whenever
possible.
The result is that after 200 iterations I did not get the
convergence with remarkable abrupt changes in ETEST during the
calculation.
Please, let me show the steps I followed for the optimization and
take a look to see if there is any obvious mistake in the procedure:
1) init_lapw (using the same parameter as in the previous
min_lapw-MSEC1-PBE optimization)
2) create case.inm_vresp (from template)
3) change NR2V to R2V in case.in0
4) a short SCF cycle to create case.r2v
5) change indxc to 28 in case.in0
6) change indxc again to 50 and save the file as case.in0_grr
7) a short SCF cycle (6 iterations ) with MSR1
8) remove case.in0_grr
9) change to MSR1a in case.inm
10) finally run_lapw -ec 0.000001 -fc 0.01 -in1orig -i 200 -it
Probably you will say that the convergence parameters are too
strict, but I found them in a paper where a similar calculation where
performed (using pseudopotentials, not lapw).
If you want, I can send you the files generated during the optimization.
All the best,
Luis
PS: some atoms where fixed through case.inM
2012/8/30 Luis Carlos Ogando Dacal <ogando at ieav.cta.br>:
> Dear Prof. Blaha, Marks and WIEN2k community,
>
> I will try the second option ("to use MSR1a and mBJ (without SO)
> and check how much the structure changes").
> As soon as possible, I will report the results.
> All the best,
> Luis
>
>
>
> 2012/8/30 Laurence Marks <L-marks at northwestern.edu>:
>> I think using mBJ and MSR1a is the idea -- is it valid/better compared
>> to just mBJ with PBE refined positions? I think it might be, but it is
>> hard to say.
>>
>> And, of course, without -so.
>>
>> On Thu, Aug 30, 2012 at 8:48 AM, Peter Blaha
>> <pblaha at theochem.tuwien.ac.at> wrote:
>>> Once again:
>>>
>>> Do you mean MSR1 or MSR1a ???? The little "a" makes a big difference
>>> and you can only compare PRATT and MSR1 for mBJ, but not MSR1a.
>>>
>>> Of course, a second try could be to use MSR1a and mBJ (without SO) and
>>> check how much the structure changes.
>>>
>>>> performance of MRS1a and PRATT when using mBJ in the band structure
>>>> calculation (as described in section 4.5.9 of the WIEN_12 Users
>>>> Guide). So, I was trying to improve the band gap and spin splittings
>>>> of the system (not to relax it) with mBJ, this is the reason why I
>>>> switched the -so option in this calculation (but not in the previous
>>>> structure optimization for the reasons you described).
>>>> Now, I know that MSR1a try to optimize the structure, what means it
>>>> is not an ordinary SCF cycle, so SOC is an unappropriated option as
>>>> you posted. I am sorry for the misunderstanding.
>>>> I will try a new structure optimization using MSR1a-mBJ with the
>>>> same parameters employed in the MSEC1-PBE case, allowing a fair
>>>> comparison between their performances. I promise to report the result
>>>> as soon as possible.
>>>> Thank you for your attention,
>>>> Luis
>>>>
>>>>
>>>>
>>>> 2012/8/30 Peter Blaha <pblaha at theochem.tuwien.ac.at>:
>>>>> For sure, forces are NOT ok when you switch on spin-orbit coupling.
>>>>>
>>>>> But please: think about the physics: InP is not that heavy and is a
>>>>> semiconductor. You do NOT need SO for any structural relaxation as
>>>>> it has negligible effects anyway.
>>>>> (However, you may NEED SO for bandstructure properties, effective
>>>>> masses,....,
>>>>> but calculate this afterwards with fixed positions, NEVER with MSR1a but
>>>>> with MSR1).
>>>>>
>>>>>
>>>>> Furthermore, in your mail it sounds as if you mixed up various schemes
>>>>> with WIEN2k.
>>>>>
>>>>> When using MSR1 you do NOT optimize positions (only "electrons"),
>>>>> MSR1a you ALWAYS will optimize positions (in fact, when you do
>>>>> not
>>>>> have case.inM, it will be generated automatically !)
>>>>>
>>>>> And for both schemes you use the command run_lapw !
>>>>>
>>>>> Alternatively, you can use min_lapw (and MSR1, not MSR1a), which will
>>>>> also optimize positions (and if case.inM does not exist, will generate
>>>>> it automatically).
>>>>>
>>>>> Both, MSR1a or min_lapw accept "constraint positions", when you execute
>>>>> x pairhess -copy (creates case.inM)
>>>>> edit case.inM and set some values to zero for constraining them.
>>>>> x pairhess -copy (so that the constrains are honored in the hessian for
>>>>> PORT).
>>>>>
>>>>> PS: At least for insulators (but usually even for difficult 3d-metallic
>>>>> systems)
>>>>> I strongly recommend MSR1a over min_lapw, as it is almost always much
>>>>> faster and more stable. The only problem left is to determine a unique way
>>>>> when to stop MSR1a (this means: what stopping criteria one should use),
>>>>> but when you accept some remaining forces (less than 5 mRy/bohr),
>>>>> even this is not a serious problem and default criteria (or even a bit
>>>>> larger value than 2.0 in case.inM) are sufficient and reasonable.
>>>>>
>>>>> PPS: When one tries MSR1a together with mBJ, I'd first converge mBJ (at
>>>>> least
>>>>> partly) with MSR1 (or PRATT and later on MSR1), and then remove
>>>>> case.in0_grr
>>>>> (this will fix the value of "c" in mBJ and make things for MSR1a more
>>>>> stable).
>>>>>
>>>>>
>>>>> Am 29.08.2012 19:03, schrieb Luis Carlos Ogando Dacal:
>>>>>
>>>>>> Dear Prof. Laurence Marks,
>>>>>>
>>>>>> Let me answer you using your previous message.
>>>>>>
>>>>>>> First, a reminder. Using MSR1a with mBJ is a computational experiment.
>>>>>>> It may not give reasonable results, or it might -- I do not know and I
>>>>>>> am not sure that anyone does, yet. The "standard" method is not to
>>>>>>> vary the atomic positions with mBJ, but this may not be optimal.
>>>>>>
>>>>>>
>>>>>> Yes, I know. I just tested MSR1a as you asked the WIEN mailing list
>>>>>> in a message you sent in August, 22. I will keep on the calculation
>>>>>> using the standard and reliable methods. My report was just a little
>>>>>> contribution to your efforts.
>>>>>>
>>>>>>> One thing to check, in your case what are the positions like in the
>>>>>>> substrate? Assuming that you have made this thick enough (e.g. 20 au
>>>>>>> or more) in the center the positions should be close to those with PBE
>>>>>>> and/or the bulk. If they are wildly different this implies that the
>>>>>>> bulk lattice parameters for PBE do not match well those from mBJ. (Of
>>>>>>> course, if you have only used 2 layers or so of substrate you cannot
>>>>>>> test this.)
>>>>>>
>>>>>>
>>>>>> Actually, I did not optimized the structure using MSR1a. I did it
>>>>>> in a previous calculation with MSEC1 and PBE with case.inM fixing the
>>>>>> substrate positions. Only after that, I used mBJ to improve the gap.
>>>>>> When I employed mBJ with PRATT (0.2 followed by 0.4 mixing factors) I
>>>>>> got the convergence in the SCF cycle and a smooth decrease in ETEST.
>>>>>> In the MSR1a test, I noticed abrupt changes in ETEST and after the
>>>>>> last iteration I got the message "energy in SCF NOT CONVERGED".
>>>>>> As I was not optimizing the structure when using MSR1a, I had not a
>>>>>> case.inM file and all the atoms changed position during MSR1a
>>>>>> calculations. Despite the fact that I used a thin substrate (I will
>>>>>> improve this in a next step), the atomic positions changed only by a
>>>>>> factor of 10^(-3) when compared to the previously PBE relaxed
>>>>>> structure (It is important to remember that MSR1a did not converged
>>>>>> and I used the last generated case.struct to compare with PBE relaxed
>>>>>> structure)
>>>>>>
>>>>>>> When you say "it did not converge with MSR1a", what exactly do you
>>>>>>> mean? It may be better to send the case.struct and case.scf files to
>>>>>>> my email directly.
>>>>>>
>>>>>>
>>>>>> I was talking about the message at the end of the MSR1a calculation
>>>>>> ("energy in SCF NOT CONVERGED"). I have not calculated any physical
>>>>>> property of the system.
>>>>>> I will send you the files in another message.
>>>>>>
>>>>>>> If you fix some atoms in case.inM, then the ones which are not fixed
>>>>>>> will move. While some people argue that this is OK, I have
>>>>>>> reservations. If you fix all the atoms in case.inM then MSR1a will
>>>>>>> crash on you -- you have to use MSR1 (or MSEC3).
>>>>>>
>>>>>>
>>>>>> All the best,
>>>>>> Luis
>>>>>>
>>>>>>
>>>>>>
>>>>>>> On Wed, Aug 29, 2012 at 7:50 AM, Luis Carlos Ogando Dacal
>>>>>>> <ogando at ieav.cta.br> wrote:
>>>>>>>>
>>>>>>>> Dear Prof. Laurence Marks (and WIEN2k users),
>>>>>>>>
>>>>>>>> I would like to report my recent experience in using MSR1a with
>>>>>>>> mBJ. I have a semiconductor system composed by In and P atoms that I
>>>>>>>> relaxed using PBE. After that, I tried the mBJ SCF cycle using PRATT
>>>>>>>> as recommended in section 4.5.9 of the WIEN Users Guide. I got the
>>>>>>>> convergence after a long cycle (strict convergence criteria), but no
>>>>>>>> convergence was obtained with MSR1a.
>>>>>>>> If you want any detail of my system and/or calculation, just send
>>>>>>>> me an e-mail.
>>>>>>>> Another point, my system tries to simulate a substrate and a cap
>>>>>>>> stressed layer. As a consequence, I need to fix the substrate atoms
>>>>>>>> during the SCF cycles. I would like to know if this can be done with
>>>>>>>> case.inM when using MSR1a (or any other way). I believe that fixing
>>>>>>>> atoms leads MSR1a to behave like MSR1. Is this right ?
>>>>>>>> All the best,
>>>>>>>> Luis Ogando
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> 2012/8/22 Laurence Marks <L-marks at northwestern.edu>:
>>>>>>>>>
>>>>>>>>> I am sure Peter had a typo - I think he meant MSR1 not MSR1a. Whether
>>>>>>>>> MSR1a
>>>>>>>>> is a good idea with mBJ is currently unclear; there was a recent
>>>>>>>>> discussion
>>>>>>>>> of this, look in the email archives.
>>>>>>>>>
>>>>>>>>> A good topic where readers of this list could contribute is testing
>>>>>>>>> whether
>>>>>>>>> MSR1a with mBJ is physically reasonable and reporting back.
>>>>>>>>>
>>>>>>>>> On Aug 22, 2012 8:47 AM, "Madhav Ghimire" <ghimire.mpg at gmail.com>
>>>>>>>>> wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Dear Prof. Marks,
>>>>>>>>>> Thank you very much for replying immediately. I was just
>>>>>>>>>> replying
>>>>>>>>>> to
>>>>>>>>>> your post.
>>>>>>>>>> As in userguide of wien2k, it is suggested to edit the case.inm and
>>>>>>>>>> change
>>>>>>>>>> MSR1a with PRATT as MSR1a leads to convergence problems in mBj.
>>>>>>>>>> Hence,
>>>>>>>>>> I
>>>>>>>>>> performed the calculations by changing MSR1a with PRATT.
>>>>>>>>>> I will follow to what you suggest right now and report within a day
>>>>>>>>>> or
>>>>>>>>>> two.
>>>>>>>>>> Please let me know more if I have to be cautious somewhere in the
>>>>>>>>>> calculations.
>>>>>>>>>> Thanks.
>>>>>>>>>> Madhav
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Wed, Aug 22, 2012 at 8:21 PM, Laurence Marks
>>>>>>>>>> <L-marks at northwestern.edu>
>>>>>>>>>> wrote:
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Can you send the case.scf file to me directly? I am curious why MSR1
>>>>>>>>>>> does
>>>>>>>>>>> not converge well for some mBJ and there are some things printed in
>>>>>>>>>>> case.scfm which may explain.
>>>>>>>>>>>
>>>>>>>>>>> ---------------------------
>>>>>>>>>>> Professor Laurence Marks
>>>>>>>>>>> Department of Materials Science and Engineering
>>>>>>>>>>> Northwestern University
>>>>>>>>>>> www.numis.northwestern.edu 1-847-491-3996
>>>>>>>>>>> "Research is to see what everybody else has seen, and to think what
>>>>>>>>>>> nobody else has thought"
>>>>>>>>>>> Albert Szent-Gyorgi
>>>>>>>>>>>
>>>>>>>>>>> On Aug 21, 2012 9:50 PM, "Madhav Ghimire" <ghimire.mpg at gmail.com>
>>>>>>>>>>> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Dear wien users and developers,
>>>>>>>>>>>> I am working on some 3d TM oxides. With a normal scf cycle
>>>>>>>>>>>> with or
>>>>>>>>>>>> without inclusion of U value, I got good convergence in energy and
>>>>>>>>>>>> charge.
>>>>>>>>>>>> This oxide material is reported to have a bandgap of approx. 0.3
>>>>>>>>>>>> eV.
>>>>>>>>>>>> In GGA,
>>>>>>>>>>>> I do not observe any gap. In the meantime even with very high value
>>>>>>>>>>>> of U,
>>>>>>>>>>>> the bandgap do not open up. Because of this, I tried to implement
>>>>>>>>>>>> mBj
>>>>>>>>>>>> potential (in order to find the bandgap) both with and without
>>>>>>>>>>>> inclusion of
>>>>>>>>>>>> U, but the energy and charge do not converge.
>>>>>>>>>>>> Rather even for a large number of iteration (199), the energy and
>>>>>>>>>>>> charge
>>>>>>>>>>>> remains constant without convergence (shown below).
>>>>>>>>>>>>
>>>>>>>>>>>> For GGA without mBj the scf cycle smoothly converges as below:
>>>>>>>>>>>> in cycle 22 ETEST: .0000236850000000 CTEST: .0038743
>>>>>>>>>>>> in cycle 23 ETEST: .0000184300000000 CTEST: .0012996
>>>>>>>>>>>> in cycle 24 ETEST: .0000174650000000 CTEST: .0006011
>>>>>>>>>>>> in cycle 25 ETEST: .0000037600000000 CTEST: .0007451
>>>>>>>>>>>> in cycle 26 ETEST: .0000016050000000 CTEST: .0001163
>>>>>>>>>>>>
>>>>>>>>>>>>> stop
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> while with mBj+GGA, energy and charge convergence remains constant
>>>>>>>>>>>> above cycle 103 and could not converge as below:
>>>>>>>>>>>> in cycle 193 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 194 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 195 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 196 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 197 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 198 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>> in cycle 199 ETEST: .2112103950000000 CTEST: 2.0591251
>>>>>>>>>>>>
>>>>>>>>>>>>> energy in SCF NOT CONVERGED
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Does anyone have experienced this type of problems. If so, please
>>>>>>>>>>>> let me
>>>>>>>>>>>> know how it can be converged. I followed all the steps as described
>>>>>>>>>>>> in
>>>>>>>>>>>> previous wien mail and userguid but could not solve.
>>>>>>>>>>>> Your help to solve this issue will be higly appreciated.
>>>>>>>>>>>> Thanks in advance
>>>>>>>>>>>>
>>>>>>>>>>>> Madhav Ghimire
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> MANA, National Institute for Materials Science (NIMS)
>>>>>>>>>>>> 1-1 Namiki, Tsukuba, Ibaraki, Japan
>>>>>>>>>>>> Phone: +81-29-851-3354 (ex.4115)
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> Wien mailing list
>>>>>>>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>>>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> MANA, National Institute for Materials Science (NIMS)
>>>>>>>>>>>> 1-1 Namiki, Tsukuba, Ibaraki, Japan
>>>>>>>>>>>> Phone: +81-29-851-3354 (ex.4115)
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> _______________________________________________
>>>>>>>>>>> Wien mailing list
>>>>>>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> MANA, National Institute for Materials Science (NIMS)
>>>>>>>>>> 1-1 Namiki, Tsukuba, Ibaraki, Japan
>>>>>>>>>> Phone: +81-29-851-3354 (ex.4115)
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Wien mailing list
>>>>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> Wien mailing list
>>>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Professor Laurence Marks
>>>>>>> Department of Materials Science and Engineering
>>>>>>> Northwestern University
>>>>>>> www.numis.northwestern.edu 1-847-491-3996
>>>>>>> "Research is to see what everybody else has seen, and to think what
>>>>>>> nobody else has thought"
>>>>>>> Albert Szent-Gyorgi
>>>>>>> _______________________________________________
>>>>>>> Wien mailing list
>>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>
>>>>>> _______________________________________________
>>>>>> Wien mailing list
>>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>>>
>>>>>
>>>>> --
>>>>>
>>>>> P.Blaha
>>>>> --------------------------------------------------------------------------
>>>>> Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
>>>>> Phone: +43-1-58801-165300 FAX: +43-1-58801-165982
>>>>> Email: blaha at theochem.tuwien.ac.at WWW:
>>>>> http://info.tuwien.ac.at/theochem/
>>>>> --------------------------------------------------------------------------
>>>>>
>>>>> _______________________________________________
>>>>> Wien mailing list
>>>>> Wien at zeus.theochem.tuwien.ac.at
>>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>> _______________________________________________
>>>> Wien mailing list
>>>> Wien at zeus.theochem.tuwien.ac.at
>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>>
>>>
>>> --
>>>
>>> P.Blaha
>>> --------------------------------------------------------------------------
>>> Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
>>> Phone: +43-1-58801-165300 FAX: +43-1-58801-165982
>>> Email: blaha at theochem.tuwien.ac.at WWW:
>>> http://info.tuwien.ac.at/theochem/
>>> --------------------------------------------------------------------------
>>> _______________________________________________
>>> Wien mailing list
>>> Wien at zeus.theochem.tuwien.ac.at
>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>
>>
>>
>> --
>> Professor Laurence Marks
>> Department of Materials Science and Engineering
>> Northwestern University
>> www.numis.northwestern.edu 1-847-491-3996
>> "Research is to see what everybody else has seen, and to think what
>> nobody else has thought"
>> Albert Szent-Gyorgi
>> _______________________________________________
>> Wien mailing list
>> Wien at zeus.theochem.tuwien.ac.at
>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
