[gmx-users] gromacs harmonic bond constant

[Vitaly V. Chaban]

Hi,

In what units does gromacs MD engine treats harmonic bond constants?
In the tutorial, there is a hint about fourth-power potential (related
to GROMOS-96 FF) which I guess should have a constant in
[kJ/mol/nm^4], but not in [kJ/mol/nm^2]. Although it seems by the
absolute value that in the existing FFs (.../top/) including GROMOS96
they appear in [kJ/mol/nm^2].

If the own FF is used, in what units should one type the values of k_b
in topology file for GROMPP to understand it correctly? My variant is
[kJ/mol/nm^2]. Please let me know if I'm true.

Thanks.
-- 
Vitaly V. Chaban, Ph.D.
http://www-rmn.univer.kharkov.ua/chaban.html