Hallo,
I am trying to calculate MP2/CC2 energy for an open-shell system using
the ROHF orbitals. The system is of a non-Abelian point group which means
there are degenerate orbitals. This seems to cause a problem when
the semicanonical transformation is done. The problem is that the reference
(HF) energy in the semicanonical orbitals is not the same as in the original
(canonical) orbitals and there is the following warning in the output:
WARNING: Energy evaluated from semicanonical
orbitals differs from reference
value in $energy !
Although the calculation goes on the resulting MP2/CC2
energies are effected, turn out to be higher than they should be.
I wonder if it is possible to circumvent/remedy the above problem.
Best regards,
Evgeniy
