[gmx-developers] modifying replica exchange to allow Hamiltonian exchanges

[Luca Bellucci]

 Thank you for the quick response.
I am sorry but I am not sure to correct understand 
"[..]is not correct unless lambda is a linear coupling parameter."
It means that, delta lambda must be equal for all replicas?
Can you provide an estimation of the next release date? 
Best,
Luca

> > I performed Hamiltonian replica exchange with gromacs 4.5.3
> > using the FEP module and the capabilty of repl_ex.c routine
> > to recognize  lambda values as replica exchange quantities.
> > I run some tests and they seems to work fine, however, I do not find any
> > documentation about it.
>
> Hamiltonian replica exchange in the 4.5.3 release version is not correct
> unless lambda is a linear coupling parameter.  A fully general version is
> being tested right now, and will likely be part of the next release.
>
> Best,
> ~~~~~~~~~~~~
> Michael Shirts
> Assistant Professor
> Department of Chemical Engineering
> University of Virginia
> michael.shirts at virginia.edu
> (434)-243-1821
>
> > From: Luca Bellucci <lcbllcc at gmail.com>
> > Date: Sat, 26 Feb 2011 05:48:56 -0500
> > To: "michael.shirts at virginia.edu" <michael.shirts at virginia.edu>,
> > Discussion list for GROMACS development <gmx-developers at gromacs.org>
> > Subject: Re: [gmx-developers] modifying replica exchange to allow
> > Hamiltonian exchanges
> >
> > Dear all,
> > I performed Hamiltonian replica exchange with gromacs 4.5.3
> > using the FEP module and the capabilty of repl_ex.c routine
> > to recognize  lambda values as replica exchange quantities.
> > I run some tests and they seems to work fine, however, I do not find any
> > documentation about it.
> >
> > Since it seems that this capability is under development, I have
> > some "uncertainty" in using it and I am not completely sure of
> > its "reliability".
> > I would like to take this opportunity to submit some questions:
> > Can I use this capability for production run?
> > Where can I find more info?
> >
> > Thank you
> > Luca
> >
> >> This has been added in a branch, and the plan is for this functionality
> >> to be included in the next Gromacs release.  We can discuss whether it
> >> would be useful for specific individual to use this test code right now,
> >> or whether it may be best to wait until there has been a chance for it
> >> to be tested more.  There area a number of other free energy changes
> >> included in this code as well.