[gmx-users] EM problem

[K.A. Feenstra]

sgaray at fbcb.unl.edu.ar wrote:
> 
> Dear Gromacs user´s
> 
> My name is Sergio Garay  and I´m trying to minimize de E of a
> bilayer of 72 stearic acid in a periodic boundary conditions. I´m
> using ffG43a2x forcefield with and without position restraints in C of
> carboxilic acids.
> Grompp preprocesator doesn´t give any warning but the EM doesn´t
> work properly (log below). It doesn´t seems to work :
> 
> Stepsize too small (7.62939e-07 nm)Converged to machine
> precision,
> but not to the requested precision (200)
> 
> Steepest Descents did not converge in 18 steps
>   Potential Energy  =  9.69202e+17
> Maximum force:          inf

Seems like you have yourself a *very* *bad* starting structure.
You should take a close look at it, there might be some (trivial?)
mix-up, like overlap of molecules, or a wrong ordering of coordinates
with respect to the topology.


-- 
Groetjes,

Anton
 ________ ___________________________________________________________
|        | Anton Feenstra                                            |
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