Subject: Orbitals

From: "Jens Spanget-Larsen" <spanget|at|virgil.ruc.dk>
Date: Wed, 28 May 2003 09:49:49 +0100

Mikael Johansson:

> On Tue, 27 May 2003, Jens Spanget-Larsen wrote:
> 
> > And in principle, MOs are not physical quantities; they are model
> > constructions, and as such they have no physical reality and they
> > cannot be observed experimentally.
> 
> Well, there is a lot of discussion in the literature on this topic.
> A few good examples, biased towards my thinking, could be:
> 
> [1] Stowasser and Hoffmann, "What Do the Kohn-Sham Orbitals and
>     Eigenvalues Mean?", J.Am.Chem.Soc. 121 (1999) 3414-3420.
> [2] Baerends, Theor.Chem.Acc. 103 (2000) 265-269.
> 
> Have a nice day,
>     Mikael J.
>     http://www.helsinki.fi/~mpjohans/

Dear Mikael,

Yes, it is true, there has been some discussion on the status of the
MO concept. But to me, there can be no doubt: In principle, orbitals
are one-electron wavefunctions, and for a many-electron system, they
do by definition NOT correspond to physical reality. However, they 
are extremely useful models, as we all know. The usefulness of the MO
concept in rationalizing a lot of chemistry and spectroscopy 
sometimes leads people to think of MOs as physical quantities, rather 
than simplified models. Do you think my point of view is erroneous?

Yours, Jens >--<

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JENS SPANGET-LARSEN         Office:         +45 4674 2710
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