Excited states polarizabilities

Hello,

Is there a way to calculate the polarizabilities of excited states? I am using the EOM-CCSD calculation. I know that the CCSD calculations have the option of making the polarizability of the ground state [properties(‘ccsd’, ‘polarizability’)], however, I needed to calculate this property for the excited states.

Best regards.

You could calculate static polarizabilities for excited states using a finite-field approach, but you’d have to be very careful about setting it up. You’d have to add the external field after the SCF calculation so that the orbital response was excluded.

Thank you @crawdad. Why do I need to be careful when doing this? Do you have an example of input or flags to take this approach?

I don’t have an example input, because I haven’t done such calculations before. You have to be careful because you want your EOM-CCSD polarizabilities for excited states to be comparable to CCSD polarizabilities of ground states. The convention for these is to exclude orbital response, and thus you have to add the external fields after the SCF step is complete so that the MOs aren’t affected. The input for this will not be as simple as for the ground state.

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Ok, thank you for the explanations!