[gmx-users] Maximum Force constant for Position Restraints

[Alex]

Correction: tau/pi on the left for the highest value and 5*tau/pi for the
10 x period suggestion above.

On Tue, Apr 21, 2015 at 1:13 PM, Alex <nedomacho at gmail.com> wrote:

> I think this can be estimated from a general physical argument. The
> absolute max in my opinion should come from
> 4*pi*tau = sqrt(m/k), where m is the mass of the lightest restrained
> particle in the system, k is the constant you seek, and tau is the
> timestep.
> The coefficient is four because of the Nyquist theorem. I believe GMX
> tests for high vibrational frequencies according to 20*pi*tau on the left
> (ten times the period).
>
> Hope this helps.
>
> Alex
>
>
> On Tue, Apr 21, 2015 at 1:02 PM, Marcelo Depólo <marcelodepolo at gmail.com>
> wrote:
>
>> Hi guys!
>>
>> Is there a maximum value of Force Constant for Position restraints?
>> Reading
>> the Manual I could only find the default and the equation to describe it.
>>
>> Best,
>> --
>> Marcelo Depólo Polêto
>> Group of Structural Bioinformatics - Center of Biotechnology
>> Student of MSc Cell and Molecular Biology - UFRGS (Brazil)
>> B.Sc. Biochemistry - University of Viçosa (Brazil)
>> --
>> Gromacs Users mailing list
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>
>