[Pw_forum] Fixing position of the atoms during the relaxation of the cell

[Pavel B Sorokin]

Dear Gabriele.

Thank you for your answer. I've digged in the forum and don't find
the answer. Yes, it seems that atomic positions are rescaling during
the cell relaxation...

About the putting of my atom in the origin.. I need to fix more than
one atom.

Anyway, thanks!

> Dear Pavel,

>    I don't know much of vc-relax, but I think that when the cell size
> is modified during the relaxation, atomic positions are rescaled  
> accordingly (I suspect I've read it in a recent post on the forum, but
> it seems quite plausible to me. Don't you think so?)
> Maybe there are some other tricks to fix some atoms (why don't you put
> that atom in the origin, for instance?), but I'm not aware of any.
> I hope someone more expert will help you better than I could, in the  
> meanwhile please try to dig a bit in the forum archives.

> Gabriele Sclauzero

> SISSA & Democritos


> Quoting Pavel B Sorokin <pbsorokin at gmail.com>:

>> Dear PWSCF community!
>>
>> I need to freeze the position of some atoms during vc-relax mode.
>> In the manual I found that I should type something like that
>>
>> ATOMIC_POSITIONS  angstrom
>> X1     x1 y1 z1 0 0 0
>> X2     x2 y2 z2 1 1 1
>> ...
>>
>> if I want to fix atom 1.
>>
>> This option works in the relax calculation but unfortunately doesn't
>> work in vc-relax mode. May you give me any tips how I can solve this
>> problem?
>>
>> Thanks!!
>>

--
Sincerely yours,
Pavel Sorokin