Dear All,

I am a Psi-4 newbie and wanted to do an RHF on the square planar H4 molecule

mol = psi4.geometry("""

H 0.45 0.45 0.0

H 0.45 -0.45 0.0

H -0.45 0.45 0.0

H -0.45 -0.45 0.0

“”")

psi4.set_options({‘basis’: ‘sto-3g’,

‘scf_type’: ‘pk’,

‘e_convergence’: 1e-8,

‘d_convergence’: 1e-8})

scf_e, wfn = psi4.energy(‘SCF’, return_wfn=True)

I think Psi-4 detects it to be of D2h symmetry and gives the SCF energy, MO coefficients, and MO energies accordingly. The orbital energies calculated by psi-4 are

-0.844036

-0.116682

0.220582

1.191747

However, I wanted psi-4 to use the full point group D4h symmetry which should give the following orbital

energies (NWChem)

-0.8440

0.0523

0.0523

1.1928

Is it possible to do full point group calculations somehow? I have read the manual which says that psi-4

reverts to the highest abelian group but I have also seen multiple publications that do D4H calculations on H4 square planar molecule using psi4! So I was wondering if there is a way to do it?