Using core Hamiltonian from previous calculation

Hi all,

it is my understanding that, even though it is possible to run multiple calculations from one input file, every time a new reference calculation is run, the core (one-particle) Hamiltonian integrals are recalculated, or at least the array is repopulated with the same elements. I have tried passing the wavefunction object to a subsequent calculation, without success, which I have also seen by scanning through the forum. I would like to know how I could use the core Hamiltonian from a previous calculation.


Unfortunately at the moment this isn’t strictly possible. For Psi4 1.3 we will be rewriting the SCF driver to enable this kind of effort. Can you describe the reason that you would like to save the core Hamiltonian, there may be another way to approach this.

Thanks for your reply!

I would like to modify the core Hamiltonian in order to incorporate some embedding potential. At this point, I have been writing the embedding potential to a file, which is read somewhere in form_H(). This is working so far, but I was wondering if there was a more elegant/efficient way to do it.

I’ll keep an eye out for Psi4 1.3 then.