[gmx-users] Enthalpy of Vaporization

[Justin A. Lemkul]

Fabian Casteblanco wrote:
> Thanks Justin.  That clarified a lot.  I'm having trouble simulating
> the 1 molecule of gas methanol.  I took the original energy minimized
> molecule and I'm trying to start it off on NVT using the following
> *.mdp file.  I got rid of PBC (ns_type=simple) and I set
> rlist=infinite.  After correcting some errors, "Can not have
> dispersion correction with pbc=no", (set dispcorr=no), and setting
> nstlist=0 since Gromacs says simulating without cut-offs is usually
> faster with nstlist=0, I now keep getting an error saying "Can not
> have nstlist<=0 with twin-range interactions".   Should nstlist be =0
> as it says in the Gromacs manual when simulating with no cut-offs for
> pbc=no?  It says I can not have Ewald with pbc=no which makes sense
> but I don't know what to replace it with.
> 

A few things:

1. "rlist = infinite" is not an option.  The value of rlist is a floating-point 
number.  To achieve infinite cutoffs, set rlist=rvdw=rcoulomb=0.

2. Don't use PME.  Set "coulombtype = cutoff."  There are no cutoff artifacts 
here, since with rcoulomb=0, all interactions are calculated.

-Justin

-- 
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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

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