[molpro-user] Helium UHF energy

Lorenzo Lodi l.lodi at ucl.ac.uk
Thu Oct 1 18:24:03 BST 2009

I was playing around with Molpro and I noticed that, for the helium 
atom, I obtain the same energy for RHF and UHF (I think UHF should be 
lower). I think that the problem is that, if the initial guess for the 
orbitals/density matrix has RHF symmetry then UHF will converge to the 
same value as RHF.
I tried to change the starting guess for UHF but, as DENSITY is not 
supported, if I'm not mistaken I can only use RHF-type orbitals (RHF or 
MCSCF ones).
Is there a way this behaviour?
I attach a very minimal input file.

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