[Wien] Problems in convergence due to application of mBj potential

[Luis Carlos Ogando Dacal]

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)
>>>>
>>>>
>>>>
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>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> MANA, National Institute for Materials Science (NIMS)
>>>> 1-1 Namiki, Tsukuba, Ibaraki, Japan
>>>> Phone: +81-29-851-3354 (ex.4115)
>>>>
>>>>
>>>
>>> _______________________________________________
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>>>
>>
>>
>>
>> --
>> MANA, National Institute for Materials Science (NIMS)
>> 1-1 Namiki, Tsukuba, Ibaraki, Japan
>> Phone: +81-29-851-3354 (ex.4115)
>>
>>
>
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