[molpro-user] how to handle single H atom at CI method

[Peter Knowles]

I agree that it's not a very graceful error message, but of course there 
is nothing for a CI program to do when there is only one electron - 
Hartree-Fock is already exact!

Peter

MHT wrote:
> Dear all,
>
> We did a test work for H atom at CI method, and got the following message 
> in the bottom. I don't know how to fix it. Thank you!
>
> 1PROGRAM * CI (Multireference internally contracted CI)     Authors: H.-J. 
> Werner, P.J. Knowles, 1987
>                                                                                                                                
>                                                                                                                                
>  Convergence thresholds:  THRVAR = 1.00D-08  THRDEN = 1.00D-06
>                                                                                                                                
>  Number of optimized states:  1  Roots:   1
>  Number of reference states:  1  Roots:   1
>                                                                                                                                
>  Reference symmetry:               1   Doublet
>  Maximum shell inside CICON        3
>                                                                                                                                
>  Maximum number of shells reduced from  3 to  1
>  Maximum number of spin couplings:      1
>                                                                                                                                
>  Reference space:        1 conf        1 CSFs
>  N elec internal:        0 conf        0 CSFs
>  N-1 el internal:        0 conf        0 CSFs
>  N-2 el internal:        0 conf        0 CSFs
>                                                                                                                                
>  Number of electrons in valence space:                      1
>  Maximum number of open shell orbitals in reference space:  1
>  Maximum number of open shell orbitals in internal spaces:  1
>                                                                                                                                
>                                                                                                                                
>  Number of active  orbitals:        1 (   1 )
>  Number of external orbitals:       4 (   4 )
>                                                                                                                                
>  Molecular orbitals read from record     2140.2  Type=MCSCF/NATURAL (state 
> 1.1)
>                                                                                                                                
>  Coulomb and exchange operators available. No transformation done.
>  MATCHING ERROR IN ICLIST, ISHELL,IR:           1           1
>  ICONRR    1                  10
>
>
>   


-- 
Prof. Peter J. Knowles              
School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK
Telephone: +44 29208 79182 Fax: +44 2920874030
Email KnowlesPJ at Cardiff.ac.uk  WWW http://www.cardiff.ac.uk/chemy/staff/knowles.html