[gmx-users] Heating the system

[Anton Feenstra]

Christoph Freudenberger wrote:
> li weihua wrote:
> 
>>Hi,all
>>  I am a new user for Gromacs. After minimization, I want to heat my 
>>system from 0K ,100K,200K to 300K in a short period(e.g.30ps). However, 
[...]
> there's nothing wrong with your mdp's, it's normal that ref_t is reached
> within a few timesteps.
> i'm just wondering why you do it that way.
> 
> If you just want to get the md started after em use:
> ref_t=300, gen_vel=yes, gen_temp=300
> (maybe use pressure coupling to allow scaling of the box)
> 
> If you really want to heat up slowly (for whatever reason)
> use a larger value for tau_t.

No - you should use the heating/cooling option provided with
the 'simulated annealing'. Check the mdp options page in the
online manual.

Beware that Berendsen T couping can result in unequally
partitioned kinetic energy. For starting normal simulations,
I'd strongly recommend to generate velocities, the way
Christoph describes.

-- 
Groetjes,

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