[molpro-user] How to alter the active space

[John Payton]

Dear MolPro Users and Authors,

I'm relatively new to Molpro and trying to run some simple CASSCF 
calculation on benzene as to teach myself. However, I'm have an issue 
with trying to achieve a 6/6 active spaces (ie, pi-system of benzene). 
HF/6-31g* places the pi orbitals at HOMO-4, HOM0-1, HOMO, LUMO, 
LUMO+1, LUMO+8. Obviously, just setting occ,24;closed,18;wf,42,1,0 
will not give me my desired active space. I'm more familiar with using 
Gaussian and MolCas, and those programs use an alter card to change 
the order of the orbitals. However, Molpro doesn't seem to have this 
function. I see in the manual the con card. I have used it 
successfully, yet it seems I'm limited only to the configuration I 
select. I want a full CI in my desired active space. How can I achieve 
this? Any suggestion will be greatly appreciated.

Thank You, 
John

 
John L. Payton
Ph.D. Candidate
Simpson Group
Department of Chemistry
Case Western Reserve University
10900 Euclid Avenue
Cleveland, Ohio  44106-7078