Dear All,
I wonder if dropping highest virtual orbitals is possible in post-HF, in particular ADC(2), calculations in Psi4. What is the keyword for that? I would appreciate very much an input example. Many thanks!
Best regards,
Evgeniy
Dear All,
I wonder if dropping highest virtual orbitals is possible in post-HF, in particular ADC(2), calculations in Psi4. What is the keyword for that? I would appreciate very much an input example. Many thanks!
Best regards,
Evgeniy
Not all method supports a frozen virtual approximation, but ADC does. The keyword is num_frozen_uocc
. For an example input file:
molecule mol {
O
H 1 1.0
H 1 1.0 2 104.5
}
set {
reference rhf
basis cc-pvdz
scf_type pk
}
energy('ADC')
set num_frozen_uocc 2
energy('ADC')
That said, be cautious about Psi4’s ADC results. There have been reports of answers from Psi not agreeing with those from Q-Chem. I don’t think we’ve traced the source of the disagreement yet.
Thank you very much for your answer and caveat regarding observed disagreement with QChem.
I also wonder, if it is possible to calculate transition dipole moments with ADC(2)?
Best wishes,
Evgeniy