On 15/06/2012 6:27 PM, Shima Arasteh wrote:
Thanks.
I read that it doesn't matter if the protein moves and even protrudes the box. It's OK, but there is a question here; why doesn't the box move rather than the protein?

The box could move, but it can't accelerate, else it wouldn't be an http://en.wikipedia.org/wiki/Inertial_frame_of_reference. I suspect the laws of motion necessary for the simulation to take place in the frame of the (accelerating) motion of the protein COM are more complex than those that take place in a simple inertial frame. So that is not done - which also avoids having to force the user to choose their inertial frame or GROMACS guessing what frame they want.

Is it possible for box to be defined every step?, then the protein would stay in the center of the box.

The box is defined at every step. If you want your solute to have a given relationship to the box every step you have to post-process your trajectory as my earlier link told you.

Mark

Sincerely,
Shima
------------------------------------------------------------------------
*From:* Mark Abraham <mark.abra...@anu.edu.au>
*To:* Discussion list for GROMACS users <gmx-users@gromacs.org>
*Sent:* Thursday, June 14, 2012 12:22 PM
*Subject:* Re: [gmx-users] protein near the edges of simulation box

On 14/06/2012 5:47 PM, Shima Arasteh wrote:
Dear gmx friends,

I put a protein in a simulation box filled of water molecules and entered the mdrun command. After the simulation, I found the protein near one of the edges of the box and not in center. What is the problem? Anyone may suggest me?
Does it mean that the simulation is meaningless?
I expect the protein to stay in the center of box and goes unfold by passing the time.

See http://www.gromacs.org/Documentation/Terminology/Periodic_Boundary_Conditions

Mark

--
gmx-users mailing list gmx-users@gromacs.org <mailto:gmx-users@gromacs.org>
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
Please don't post (un)subscribe requests to the list. Use the
www interface or send it to gmx-users-requ...@gromacs.org <mailto:gmx-users-requ...@gromacs.org>.
Can't post? Read http://www.gromacs.org/Support/Mailing_Lists




-- 
gmx-users mailing list    gmx-users@gromacs.org
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at 
http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
Please don't post (un)subscribe requests to the list. Use the 
www interface or send it to gmx-users-requ...@gromacs.org.
Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

Reply via email to