[gmx-users] FW: about atom perturbation in TI

[K.A. Feenstra]

Alexey Romanov wrote:
 >
> OPLS nonpolar H have charges and VdW parameters.
> I just tested butane. Always zero free energy!
> In my case every atom in butane have charge and VdW parameters.
> But energy is zero in perturbing either charges or VdWs to zero.
> Strange thing.

Do you have any non-zero internal energy groups?
Check your logfile or g_energy.


-- 
Groetjes,

Anton
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