[gmx-users] COM motion removal problem

[K.A. Feenstra]

Nguyen Hoang Phuong wrote:
> 
> Should we remove the overall rotation of the system after simulations
> (not at every step) by using least-squares fit?

Not 'should'. You can if you want to. It depends on what you want to
look at for your specific system. For many properties, overall rotation
is not relevant, and can safely be ignored. For others, it interferes
(e.g. viewing a trajectory) and could be removed. If you want to do
it, the easiest and most often used way is by fitting.

For vacuum simulations, however, you can get 'spinning ice cubes',
i.e. all kinetic energy of your system accumulates in the rotation.
(see one of Eric's mails for more info).


-- 
Groetjes,

Anton
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