[gmx-users] About Simulated Annealing

[Anton Feenstra]

Weihua Li wrote:
> Hi all,
>   I want to perform a MD with simulated annealing.But i don't know how to use the parameters in .mdp file(e.g. cooling down from 500k to 100k).It seems to only have a parameter that cooled down to 0K,Zero_temp_time. 
> How to control the system to cool down to 100K?
>  Could anyone give me some suggestions? Thank you very much!

Simple: stop your simulation as soon as the temperature reaches
100K, then continue with regular T-coupling w/o simulated anealing.

i.e. you would do something like:
grompp -f cool.mdp -o cool.tpr
mdrun -f cool.tpr -o cool.trr
grompp -f 100K.mdp -t cool.trr
mdrun
(I might have some of the option names wrong,
check for a trajectory input for grompp.)
In cool.mdp you should tune nsteps such that at the final
step your simulated annealing will have dropped to 100K.

-- 
Groetjes,

Anton
 _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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|             | Feenstra at chem.vu.nl - www.chem.vu.nl/~feenstra/       |
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