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Re: [lammps-users] fix deform alternate
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Re: [lammps-users] fix deform alternate


From: Michael King <michael.king@...5650...>
Date: Wed, 6 Dec 2017 15:52:19 +0100

from the manual:

For style scale, a multiplicative factor to apply to the box length of a dimension is specified. For example, if the initial box length is 10, and the factor is 1.1, then the final box length will be 11. A factor less than 1.0 means compression.

So if you have already placed atoms on a lattice in it, their positions will be scaled too. If you create them afterwards but have invoked the lattice command before, i don't know. Just test it with the in.lj script...should take you 5 mins to get the answer without asking random guys on the internet.

Concerning fix wall affecting your results, for sure it will. How? I don't know.

Micha

On 06/12/17 15:18, Rajesh wrote:
Dear King,
Does box_change scale command also reduces the lattice constant in case of
solids? I am using it on polymer and graphene sheet system. If I reduce
system size to increase density, it reduces the lattice constant of
graphene.

On Tue, Dec 5, 2017 at 10:55 PM, Rajesh <creativeidleminds@...24...> wrote:

Dear Michael
Again thanks for ur quick response. I am not sure about fix wall command.
how it will affect my results.

On Tue, Dec 5, 2017 at 10:27 PM, Michael King <
michael.king@...5650...> wrote:

Since you want to have a wall where they can't move through:
"fix wall" is what you are looking for.
Same goes for the rest, just screen the documentation (
http://lammps.sandia.gov/doc/Section_commands.html#individual-commands)
for keywords related to what you want to do and read the page.
They will point out the usage / limits etc. Thats the easiest way to
learn it and faster then waiting for others to answer

Micha


On 05/12/17 15:19, Rajesh wrote:

Dear Dr King,
After changing the box, I am getting desired density by shrinking the
box.
But since I am using s p p, box again expands if I equalibrate it. Is
there
any way to hold the atoms inside the shrunk box while equalibration?

On Dec 5, 2017 7:45 PM, "Michael King" <michael.king@...5650...>
<michael.king@...5650...> wrote:

Dear lammps users,
Is there any way in lammps to shrink or expand a dimension with
non-periodicity? Since fix deform can not be used on non-periodic
boundaries, I can't use it.

Thank you.


Rajesh


Just do manually what fix deform does for you.


boundary s p p
...
label loop_shrink
    variable n loop 10
    change_box all x scale 0.5 remap
    ...
    next n
jump SELF loop_shrink

Copy in.lj and modify it to test it.
Next time just check related commands and you can figure it out by
yourself


--
Ph.D Candidate
Computational Chemistry
University of Konstanz, Germany

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--
Ph.D Candidate
Computational Chemistry
University of Konstanz, Germany


------------------------------------------------------------
------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
lammps-users mailing list
lammps-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/lammps-users



--
Ph.D Candidate
Computational Chemistry
University of Konstanz, Germany