Get R amplitudes an in CCEOM

Dear Developers,

In the module of CCEOM, is it possible to get the wavefunctions parameters of the excited states (Like the R amplitudes) beyond what is printed ?

best,

Ricardo Almada Monter

You will have to modify the source code. The EOM equations are solved in
psi4/psi4/src/psi4/cc/cceom/diag.cc

Look for the “amp_write” functions at the bottom - those are the ones that print the largest contributions to the output file. But that block of code shows you how to access the R amplitudes.

Also, do you need this to see large amplitudes, or to feed this into another program?

Thanks for the prompt replay @jmisiewicz and @Rollin_King. Yes, the idea is to be able to feed them to other programs to replicate the results.

I don’t know what you intend to do with the amplitudes. But if you just want to make sure that different programs agree with one another, then you can just compare the excited state energies, no?

That is True. I am working in a database of excited states and I was expecting to make this amplitudes available in combination with other wavefunction parameters to make the results more reproducible.