[gmx-users] em step

[K.A. Feenstra]

sadhna wrote:
 > hi all,
 >        while doing vacuum energy minimisation with em step=0.01nm
 > I get the following:
 >
 > Stepsize too small (9.91837e-07 nm)Converged to machine precision,
 > but not to the requested precision (100)
 >
 > Could any one suggest  solution to this.

It's not a problem, so there is no solution.

Having said that, what the message means is that, up to the accuracy
of the calculation, it has converged, although your convergence
criterium based on maximum force has not (yet) been reached. It might
be that it is not possible to go lower for your system, or it might
be that you need to 'stir' it a little before you can go lower.
You could do a bit of MD at low temperature (say, 100K), and then
minimize. If your only goal is to minimize so you can start a run,
just start one (at your normal settings). If it runs OK, all is OK.


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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