I have a question related to a SA2-CAS(2,2) calculation using cistep=ALDET and ISPIN=0.
I am interested in two singlet states, S0 and S1. Even with NSTGSS=4
the calculation crashes with the error:
***** ERROR *****
THIS RUN FOUND 1 CI EIGENVECTORS WITH S= 0.00,
BUT YOU REQUESTED STATE AVERAGING OF 2 ROOTS.
PLEASE EXAMINE YOUR CHOICE OF -NSTATE- INPUT DATA.
So, I wonder if cistep=ALDET can be used in such a case, or only cistep=GUGA works here?