[gmx-users] AFM pulling of two groups

[Justin MacCallum]

> Thanks for your reply.
> I verified the force constants for the afm pulling were both specified:

It looks like your ppa file is correct

> I'm working with a single large molecule (a polymer network) and the groups
> are parts of it. I built the network by assemblying different chains and
> jointing them by chemical bonds. Now I should shrink the system to the
> correct density and the pull facilities seem very promising.
> 
> I use no constraints and a time step of 0.5 fs. Is it a problem to have
> groups part of the same molecule, with the 3.2.1 version?
> 

I don't believe that it should be. I believe there is a bug which
presents a problem for pulling more than one group. I believe that this
his been fixed in the CVS version but I'm not positive. Its in the file
pullio.c if I remember correctly. If you search the developer mailing
list you should be able to find the required patch.

Justin

-- 
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Justin MacCallum	PhD Student
Biocomputing Lab	Department of Biological Sciences
University of Calgary	http://moose.bio.ucalgary.ca
jlmaccal at ucalgary.ca	(403) 220-2264
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