[gmx-users] Changing Ionic strength in gromacs

[Miguel Machuqueiro]

Hi all,

I'm posting this message for a 2nd time hoping that someone (developers!!!) 
can give me a hint.

I would like to know how Gromacs calculates the Ionic Strength of my system 
(protein + solv + ions)?

The manual only refers to the Generalized-Reaction-Field and mentions:

"The ionic strength is computed from the number of charged (i.e. with non 
zero charge) charge groups"

Running a small MD and checking the output, it shows:  I = 0

It seams to me that with or without counterions, Gromacs is setting the 
Ionic Strength and kappa to zero, is this correct?

Thank you,

=========================================
Miguel Machuqueiro
ITQB-Instituto de Tecnologia Química e Biológica
     Universidade Nova de Lisboa
Molecular Simulation Group - 6º Floor (Room 601)
Av. da República, EAN, Apartado 127
2781-901 Oeiras, Portugal
Tel. : +351 214469618 /Mobile: +351 96 7562285
E-mail1: machuque at itqb.unl.pt
E-mail2: masm at fc.ul.pt
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