fancy2012 wrote:
 Dear Mark,
I know that the tutorial can go through, my problem is just how to generate the two topology files. From the tutorial, I know how to run TI calculation, but first, I got to know how to prepare these files, both for topology and coordinate files. I will highly appreciate for your suggestion if you can help me! Thanks!

Be advised that calculating free energies in Gromacs-4.0.x is different from the instructions in the tutorial, which are for version 3.3.x; topology manipulation is no longer necessary and the methods for decoupling are controlled by settings in the .mdp file. You haven't said which version of Gromacs you're using, but that is quite important. There are several threads in the list archive that discuss free energy calculations in Gromacs-4.0.x. There are no tutorials, however. There are various programs in the User Contribution section of the Gromacs site for generating small molecule topologies, as well as the PRODRG server for Gromos topologies. The parameters that any of these programs give are not necessarily 100% reliable (especially in the case of PRODRG).

Generating a coordinate file is going to depend on what you're doing. If you have a simple small molecule in water, you'll have to have some initial configuration for the solute and there are many tools that can be used for that purpose. Solvent can be added with genbox. But since you haven't given any details of what it is that you're trying to accomplish, that's about as precise as any advice can get.

-Justin

All the best,
Qinghua
Date: Wed, 14 Apr 2010 00:09:16 +1000
From: Mark Abraham <[email protected]>
Subject: Re: [gmx-users] How to prepare the two tolopogy files when
        doing   TI      calculation?
To: Discussion list for GROMACS users <[email protected]>
Message-ID: <[email protected]>
Content-Type: text/plain; charset=x-gbk; format=flowed

On 13/04/2010 7:35 PM, fancy2012 wrote:
> Dear GMX users,
> I want to do some TI calculation using GMX, and I have learned the
> tutorial of TI calculation from this web site
> http://www.dillgroup.ucsf.edu/group/wiki/index.php/Free_Energy:_Tutorial.
> So I have know how to run TI calculations. But there is still a problem.
> I don't know how to prepare the two topology files, which are initial
> and final states, respectively. Could somebody give me some suggestion
> on it? Any response will be highly appreciated! Thanks!

Didn't the tutorial go through that? Look at its examples.

Mark


--
========================================

Justin A. Lemkul
Ph.D. Candidate
ICTAS Doctoral Scholar
MILES-IGERT Trainee
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

========================================
--
gmx-users mailing list    [email protected]
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting!
Please don't post (un)subscribe requests to the list. Use the www interface or send it to [email protected].
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

Reply via email to