[QE-users] calculation stops after bfgs step without writing atom coordinates

[Antonio Cammarata]

Hi Kazume,

Il 01. 06. 24 14:10, Kazume NISHIDATE ha scritto:
> Hi, Antonio
>
>> After few geometric steps, I'll start to reduce the spread gradually
>>   until zero and decrease the number of bands to speedup the
>>   calculation.
> This may be the origin of your problem.
> You should go back to your previous setting.
Which problem do you refer to exactly? The memory problem?
>
> my last comment:
>   You should not apply 'peculiar setting' until you can fully
>   understand what you are doing.

Can you please be more precise? This would help me to understand what I 
am missing here. If you refer to the reduction of the number of bands, 
of course, I will keep into account the accuracy of the converged 
solution and keep in mind that, depending on the algorithm, the last 
bands (usually 2 unless otherwise specified) are used as a buffer and 
converged with a tolerance larger than that specified in the input. 
Also, the number of bands will be such that few empty bands are present 
above the Fermi level.

Antonio

>
>
>> 2024/06/01 19:27、Antonio Cammarata <cammaant at fel.cvut.cz>のメール:
>>
>> Dear Kazume,
>>
>> thanks for your reply. Yes, I tried the default settings as very first run. Since in the first geometric steps I expect a metallic cluster due to the unsaturated bonds, I had to use a large gaussian spread; for this, I increased the number of empty bands. Since this spread is large, the number of bands is still not enough to see null occupation in the last bands. After few geometric steps, I'll start to reduce the spread gradually until zero and decrease the number of bands to speedup the calculation. I will still need a couple of empty bands to have an idea of the band gap about the Fermi level.
>>
>> Antonio
>>
>> Il 31. 05. 24 14:37, Kazume NISHIDATE ha scritto:
>>> Hi, Antonio
>>>
>>> a note from the manual:
>>> -----------------
>>> nbnd INTEGER
>>> Default: for an insulator, nbnd = number of valence bands (nbnd = # of electrons /2);
>>> for a metal, 20% more (minimum 4 more)
>>> ————————
>>>
>>> https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm277
>>>
>>> You should try to use the default setting as much as possible
>>> for first. It is a best way to untangle a confused problem.
>>>
>>>
>>> good luck
>>>
>>>
>>>
>>>> 2024/05/31 20:07、Antonio Cammarata via users <users at lists.quantum-espresso.org>のメール:
>>>>
>>>> 1. Yes, once the bulk structure is truncated, the dangling bonds have the effect to close the gap; so in the first steps of the optimisation I expect the system to be metallic until surface reconstruction occurs. I'll reduce it during the relaxation.
>>>>
>>>> 2. Yes, because the structure in the input is obtained by truncating the periodic bulk and atoms are not at the equilibrium yet.
>>>>
>>>> Can you please advide on how to solve the memory issue and to provide optimal parallel parameters?
>>>>
>>>> Thanks a lot in advance
>>> 西館数芽
>>> Kazume NISHIDATE Ph.D
>>>
>>> Department of Systems Innovation Engineering,
>>> Graduate School of Science and Engineering, Iwate University
>>> 4-3-5 Ueda, Morioka, Iwate, 020-8551 JAPAN
>>> Phone:+81-19-621-6391
>>> kazume.nishidate at gmail.com, nisidate at iwate-u.ac.jp
>>> https://sites.google.com/site/nisidatelab/
>>>
>> -- 
>> _______________________________________________
>> Antonio Cammarata, PhD in Physics
>> Associate Professor in Applied Physics
>> Advanced Materials Group
>> Department of Control Engineering - KN:G-204
>> Faculty of Electrical Engineering
>> Czech Technical University in Prague
>> Karlovo Náměstí, 13
>> 121 35, Prague 2, Czech Republic
>> Phone: +420 224 35 5711
>> Fax:   +420 224 91 8646
>> ORCID: orcid.org/0000-0002-5691-0682
>> ResercherID: A-4883-2014
>>
> 西館数芽
> Kazume NISHIDATE Ph.D
>
> Department of Systems Innovation Engineering,
> Graduate School of Science and Engineering, Iwate University
> 4-3-5 Ueda, Morioka, Iwate, 020-8551 JAPAN
> Phone:+81-19-621-6391
> kazume.nishidate at gmail.com, nisidate at iwate-u.ac.jp
> https://sites.google.com/site/nisidatelab/
>
-- 
_______________________________________________
Antonio Cammarata, PhD in Physics
Associate Professor in Applied Physics
Advanced Materials Group
Department of Control Engineering - KN:G-204
Faculty of Electrical Engineering
Czech Technical University in Prague
Karlovo Náměstí, 13
121 35, Prague 2, Czech Republic
Phone: +420 224 35 5711
Fax:   +420 224 91 8646
ORCID: orcid.org/0000-0002-5691-0682
ResercherID: A-4883-2014