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<TITLE>RE: [gmx-developers] Re: UFF in Gromacs and PBC</TITLE>
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<P><FONT SIZE=2>-----Original Message-----<BR>
From: gmx-developers-bounces@gromacs.org on behalf of David van der Spoel<BR>
Sent: Wed 3/29/2006 12:16 PM<BR>
To: Discussion list for GROMACS development<BR>
Subject: Re: [gmx-developers] Re: UFF in Gromacs and PBC<BR>
<BR>
<BR>
> Is anyone working on adding the Universal Force Field, UFF, to GROMACS?<BR>
> I am interested in using GROMACS to model a slightly different system to<BR>
> that which most people seem to use it for, namely for modelling<BR>
> thioalkane self-assembled monolayers. I have added a Fourier expansion<BR>
> angle function to GROMACS-3.2.1, which is necessary for the UFF. I did<BR>
> this by basing it on the Ryckaert-Belleman's function (to get something<BR>
> akin to a Fourier expansion in theta) and the angle function to get<BR>
> theta and dthetadr. Would it be of interest to you to add the UFF to<BR>
> GROMACS?<BR>
Yes, but it depends on the amount of work needed. Is it only this extra<BR>
angle function? How about force field parameters? Doesn't UFF in<BR>
principle cover the whole periodic table? How about all possible angle<BR>
and torsion potentials?<BR>
<BR>
<BR>
Well, there is also an extra improper torsion, which is also a Fourier expansion and should be easier to add than the UFF Angle was (I hope as I intend to add it at some point in the future). UFF does cover the whole periodic table. Thus far I have just put in atoms I need for the force-field. The parameters are mostly generated from a set of simple rules. At the moment (as I only need 5 atom types) I have been generating all the parameters by hand, but a script could easily do that part. </FONT></P>
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