Exchange and Coulomb components in HF energy

Does anyone know of a simple, existing way to get the Coulomb and Exchange energy components to the HF energy?

It looks like the Coulomb and Exchange energies are added together almost instantly upon computation. You’d either have to modify the compute_E functions in libscf_solver to store those contributions to variables or get the electron repulsion integral tensor and the orbital coefficients and manually compute the Coulomb and exchange components, Psi4Numpy style.

See here for an example.

Thanks to both of you. It’s peculiar that our output file contains the “exchange gradient” but no one seems to have ever wanted to know the exchange energy. Of course I was wondering if this data was already printed or stored somewhere. I will implement something like you suggest. Thanks again.

I don’t see an “exchange gradient”, you might be referring to the exchange contributed to the nuclear gradient?

Yes, that’s what I saw.

But you are asking about energy? The two are not really comparable.

My mistake then. I haven’t thought through the gradient contributions in awhile. But, yes, it’s the energy I’m interested in.

For organizational purposes, I marked this question as solved. If it isn’t solved, let me know, and I can undo it.

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