[gmx-users] Re: Can you help me?

[Anton Feenstra]

Dr. Dong XY wrote:

> Hello, K. Anton Feenstra
>    I'm a student of Tianjin University of China. I want to get the chemical
> unfolding structure of protein.But I can't minimize the mixture. I always get the
> following cues:
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Stepsize too small, or no change in energy.
> Converged to machine precision,
> but not to the requested precision Fmax < 1000
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> I try so many ways, but they doesn't waork. Can you tell me what did you do?
> Thank you in advance and best wishes! 

This is not necessarily a problem. You should look at the final energy. 
Is it low enough? Also, you can look at the separate energy terms, like 
angles, dihedrals, Lennard-Jones, and so. You can find these in the 
logfile from mdrun (usually 'md.log').


-- 
Groetjes,

Anton

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