[molpro-user] Question about FCI calculation

[Peter Knowles]

This example uncovers a bug in the code that finds the FCI eigenvalue. The bug is triggered by an unusual, but not incorrect, numerical condition.  It has now been fixed in the developer version of Molpro, and will appear in 2009.1 in due course after testing.
Peter
On 6 Apr 2010, at 21:37, Sandipan Banerjee wrote:

> Dear Molpro-users,
> 
> I am trying to calculate the $\Pi_{u}$ state of Be$_{2}^+$ dimer. When I run a point at a separation of 10 bohrs, the FCI program simply hangs. I am using Dunning's cc-pVTZ basis and doing an all electron valence FCI calculation.
> 
> It is also strange that this same input file runs successfully at other points say at 9.8 bohrs and then fails again at 10 bohrs. So it is very strange that I can run few points on the grid, and then others I can't. Attached are the input and output files.
> 
> Any help in this regards would be highly appreciated.
> 
> Thanks
> 
> Sandipan Banerjee
> Grad Student
> Dept. of Physics
> Univ. of Connecticut
> Storrs, CT 06269
> 
> !
> ***,be2+
> 
> memory,250,M
> basis=vtz
> 
> d = [9.8,10.0]
> 
> do i=1,#d
> geometry={ be; be 1 d(i) }
> set,charge=1
> {rhf;wf,7,3,1}
> fci
> enddo
> 
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--
Prof. Peter J. Knowles             
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