[gmx-users] question about compass ff

[David van der Spoel]

On 6/2/10 2:40 PM, Justin A. Lemkul wrote:
>
>
> Andrei Neamtu wrote:
>> Justin, thank you.
>>
>> In fact I am worried about the cross coupling terms which apper i the
>> functional form of COMPASS and CVFF.
>>
>> As far as I know in GROMACS there are no such terms, so I am asking if
>> there might be a solution to include these by editing .itp, nb.itp,
>> bon.itp, .rtp, etc, without the need to modify the gromacs CODE.
>>
>
> These are very complicated functional forms, indeed. You may be able to
> use tabulated bonded potentials, but I don't have much experience in
> that arena, so I don't know if even that would be possible.
>

Have you checked the manual? There are some cross coupling functions for 
bonds/angles. I don't know what Compass wants though.

> -Justin
>
>> Andrei
>>
>> On Wed, Jun 2, 2010 at 2:23 PM, Justin A. Lemkul <jalemkul at vt.edu> wrote:
>>>
>>> Andrei Neamtu wrote:
>>>> Dear all,
>>>>
>>>> does anyone know if it is possible to somehow use COMPASS or CVFF
>>>> forcefields in Gromacs?
>>>>
>>> You can probably implement just about anything by creating the right
>>> files
>>> (.itp, nb.itp, bon.itp, .rtp, etc). Quite a bit of work, but not too
>>> conceptually difficult. Whether or not there need to be changes to the
>>> source code to accommodate new force fields may be another issue.
>>>
>>> -Justin
>>>
>>>> Thanks,
>>>> Andrei
>>> --
>>> ========================================
>>>
>>> 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 gmx-users at gromacs.org
>>> 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 gmx-users-request at gromacs.org.
>>> Can't post? Read http://www.gromacs.org/mailing_lists/users.php
>>>
>>
>


-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205. Fax: +4618511755.
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se