[gmx-users] Ion self-interaction energy?

[Leandro Bortot]

Dear users,

     I simulated system consisting of a protein complexing a single calcium
cation. I used explicit water and ions (Na+ and Cl-) in the solution to
neutralize the charge and mimic ionic strenght effects.

     I was investigating some interactions and found that if I select the
energy term "Coul-SR:CA-CA" with g_energy I got a constant value of
-979.327 kJ/mol. I checked and the "CA" group indeed correspond to the
single Ca2+ in the simulation.
    What is the meaning of this "self-interaction" energy? How should I
interpret it?


Thank you for your attention,
Leandro