$MOFRZ group    (optional, relevant for RHF, ROHF, GVB)
 
    This group controls freezing the molecular orbitals
of your choice during the SCF procedure.  If you choose
this option, select DIIS in $SCF since SOSCF will not
converge as well.  GUESS=MOREAD is required in $GUESS.
 
FRZ   = flag which triggers MO freezing. (default=.FALSE.)
 
IFRZ  = an array of MOs in the input $VEC set which are
        to be frozen.  There is no default for this.