[molpro-user] SCF vs CASSCF orbitals

[David Ambrosek]

I have a general question. Maybe somebody might be able to help me. I have 
run two jobs on a large organometallic molecule; a SCF and a MULTI job.

The orbitals of the SCF job were analysed and I picked my active space 
using the following input lines.

OCC,36,16;
CLOSED,27,11;

I assumed that CASSCF would simply take the orbitals numbered 28.1, 29.1, 
30.1 ...36.1 for the A' symmetry and similarly the orbitals 12.2, 13.2, 
..16.2 for the A'' symmetry.

However in comparing the energies and the orbitals printed out using 
Molden, not all of the orbitals are similar.

So the question:

Does the MULTI program pick the orbitals himself that he wants in the 
active space? Or is it really true that he uses those specific orbitals 
and then optimizes them.

Thanks in advace for any help.
David Ambrosek