[molpro-user] MRCI: MORE STATES THAN REFERENCE CONFIGURATIONS

[wielgus at mml.ch.pwr.wroc.pl]

Dear MOLPRO Users,

I'm trying to calculate MRCI for B2 molecule using D2h symmetry. Since I
need to follow some restriction when preparing the CAS wavefunction for
MRCI, the sigma(g) and sigma(u) are excluded from active space. It is set
on all other valence space. For this I prepared such CI input:

CI
 OCC,2,1,1,0,2,2,2,0
 CLOSED,2,0,0,0,2,0,0,0
 CORE,0,0,0,0,0,0,0,0
 WF,10,3,2
 ORBITAL,2100.1
 STATE,1

The output says:
 MORE STATES THAN REFERENCE CONFIGURATIONS:     1    0

What is the reason? The strangest thing is that I encountered exactly the
same problem when doing CAS calculations in MOLCAS, but it occurs only for
triplet states...

Thank you in advance,

Pawel Wielgus