[Pw_forum] [EXTERNAL] Re: How to reuse cell geometry for successive straining of a lattice

[xirainbow]

Dear Jon,
        I hope this is what you want :)
        http://blog.sina.com.cn/s/blog_5f15ead20101r5uv.html

On Fri, Jan 24, 2014 at 9:08 AM, Zimmerman, Jonathan A
<jzimmer at sandia.gov> wrote:
> Thank you Axel, I will give your first suggestion a try and let you know
> if I need the elaborate option.
>
> Many thanks and regards,
>
> Jon
> ----------------------------------
> Jonathan A. Zimmerman
> Principal Member of Technical Staff
> Mechanics of Materials Department
> Sandia National Laboratories
> P.O. Box 969 - MS 9957
> Livermore, CA 94551
>
> Tel: (925) 294-2437 or (800) 4SANDIA x4-2437
> Fax: (925) 294-2355
> E-mail: jzimmer at sandia.gov
> ------------------------------------------
>
>
>
>
>
> On 1/23/14 2:14 PM, "Axel Kohlmeyer" <akohlmey at gmail.com> wrote:
>
>>On Wed, Jan 22, 2014 at 9:06 PM, Zimmerman, Jonathan A
>><jzimmer at sandia.gov> wrote:
>>> Hi Pw_forum folks,
>>
>>hi jon,
>>
>>> I'm new to Quantum Espresso, but I have checked the archives and I don't
>>> think this question has been asked (at least not this way). Here goes:
>>>
>>> I'd like to perform a series of vc-relax calculations on a crystal
>>>lattice
>>> such that each time I increase the amount of applied strain in a given
>>> direction (via the CELL_PARAMETERS), from one calculation to the next I
>>> reuse the other, unconstrained CELL_PARAMETERS and the ATOMIC_POSITIONS.
>>> This way, my Poisson contraction and non-uniform relaxation of the
>>>atoms is
>>> done gently, rather than restarting each calculation with the same
>>> 'unrelaxed' ATOMIC_POSITIONS. I'm hoping that a few of you have done
>>> something similar and have a script or suggestions for carrying-over the
>>> CELL_PARAMETERS (those I'm not fixing) and ATOMIC_POSITIONS from one
>>> calculation to the next. If so, please respond.
>>
>>since nobody else responded to your question here are a few thoughts on
>>that:
>>
>>what you want to do should be easily doable with a little bit of
>>scripting. i suggest you have a look at the pwo2xsf.sh script that can
>>be used to extract coordinates from a QE run into an .xsf file, which
>>contains coordinates and cell vectors. similarly, there is xsf2pwi.sh,
>>that would convert a set of .xsf coordinates to a format suitable for
>>input of pw.x. if you write a little script to process a given input
>>file template, then you can combine these two scripts with your script
>>and do the processing as you intend to do.
>>
>>it might also be possible to combine this.
>>
>>another, more elaborate, option would be to adopt the new "COUPLE"
>>interface that allows to interface pw.x in a (superficially) similar
>>fashion as you know it from LAMMPS. so you could make it run a
>>repeated relaxation output the final coordinates, modify, and
>>continue. this code is only available through the svn currently. but
>>if you want to go this route, please contact me off-list and i'd be
>>more than happy to collaborate with you to write a little "driver" for
>>your needs.
>>
>>best regards from philly,
>>
>>    axel.
>>
>>>
>>> Thanks!
>>>
>>> Jon Zimmerman
>>> ----------------------------------
>>> Jonathan A. Zimmerman
>>> Sandia National Laboratories
>>> E-mail: jzimmer at sandia.gov
>>> ------------------------------------------
>>>
>>>
>>> _______________________________________________
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>>
>>
>>--
>>Dr. Axel Kohlmeyer  akohlmey at gmail.com  http://goo.gl/1wk0
>>College of Science & Technology, Temple University, Philadelphia PA, USA
>>International Centre for Theoretical Physics, Trieste. Italy.
>>_______________________________________________
>>Pw_forum mailing list
>>Pw_forum at pwscf.org
>>http://pwscf.org/mailman/listinfo/pw_forum
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum



-- 
____________________________________
Hui Wang
School of physics, Henan University of Science and Technology, Henan, China