CCL: Spin contamination increased by annihilation of the first-order contaminant

[Víctor Luaña Cabal <victor,+,fluor.quimica.uniovi.es>]

 Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal
 [victor%x%fluor.quimica.uniovi.es]
 On Fri, May 01, 2015 at 06:00:58PM +0300, Igors Mihailovs
 igors.mihailovs0::gmail.com wrote:
 > I was quite surprised when, during stability analysis of my wavefunction
 > and subsequent reoptimization of it in unrestricted space, the spin
 > contamination was not descreased by removal of the first-order contaminant:
 >  The wavefunction has an RHF -> UHF instability.
 >  The two search directions are symmetric.
 > Is there some way to interpret this result?
 Sorry, no simple to say without knowing any other thing about your
 problem, but a Jahn-Teller effect corresponds to the data available.
 Regards,
        Dr. Víctor Luaña
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 ! Dr.Víctor Luaña, in silico chemist & prof. !
 ! Departamento de Química Física y Analítica !
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