$SODET group                 (required if CITYP=FSOCI)                          
    This group controls a full second order CI calculation                      
using determinants (see also the keyword SOCI in $CIDRT).                       
Most of the characteristics of the active space (such as                        
NCORE, NACT, NELS) must be given by $CIDET input, as a                          
preliminary full CI according to $CIDET will be made.  The                      
FCI states will then used as the initial guess for the full                     
second order CI.  A few additional parameters may be given                      
in this group, but many runs will not need to give any of                       
NEXT   = the number of external orbitals to be included.                        
         The default is the entire virtual MO space.                            
NSOST  = the number of states to be found in the SOCI.                          
         The default is copied from NSTATE in $CIDET.                           
MAXPSO = maximum expansion space size used in the SOCI.                         
         The default is copied from MXXPAN in $CIDET.                           
ORBS   = MOS means use the MCSCF orbitals, which should be                      
             allowed to undergo canonicalization (see the                       
             CANONC keyword in $MCSCF), or the input $VEC                       
             group in case SCFTYP=NONE. (default)                               
         NOS means to instead use the natural orbitals of                       
             the MCSCF.                                                         

generated on 7/7/2017