Posted by Björn Roos on March 25, 2009 at 10:37:59:
In Reply to: CASSCF calculation posted by eduard cremades on March 24, 2009 at 18:56:26:
The ground state of Co(2+) is 4F, 7-fold degenerate. The next state is 4P, 3-fold degenerate. You have to do a state average CASSCF calculation with 10 roots (7+3) and a corresponding MS-CASPT2 calculation (use the keyword NOMULT to speed it up). The result should be 7 roots of one energy and 3 of the second with an energy difference of about 15000 cm-1 (there might be a slight symmetry breaking which one can simply average out). You can do the same for the doublet states but here you have many more states to average over: 9+11+5 for 2G, 2H, and 2D, respectively. Spin-orbit splittings can be computed by RASSI with the above states as input.
Good Luck
Best regards
Björn Roos