Getting the potential energy of a subsystem

[Simone Ritarossi]

Dear all,

I am simulating (MD) a system consisting of two well-defined subsystems. Clearly from the output I can know the total potential energy and the total kinetic energy. I would like to be able to obtain the potential energy of a subsystem (as a list of atoms?).
(Kinetic energy can be calculated from TEMP_KIND, no problem).

I really appriciate your help.

Best regards,
Simone

[Jürg Hutter]

Hi

such an energy decomposition is not unique as you have to decide what to do
with the interaction energy.
In CP2K available are Atomic Energy Decompositions

FORCE_EVAL / PROPERTIES / ATOMIC / ENERGY

and

FORCE_EVAL / DFT / PRINT / ENERGY_DECOMPOSITION_ANALYSIS

If one or both of these options is available depends on what method
you are actually using.

regards
JH

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[Simone Ritarossi]

Thank you for your reply.

My goal is to obtain the potential energy of only one part of my system. During MD, for each timestep, I have the total potential energy and the total kinetic energy. Can I obtain (or reconstruct) the potential energy of only one group of atoms in my system?

I have tried both recommended options, but I get 1) either overly detailed information or 2) a 'total atomic energy' and not that of a subsystem.


Thank you very much for your help!