From chemistry-request # - at - # ccl.net Tue May 27 15:01:58 2003
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Date: Tue, 27 May 2003 22:01:51 +0300 (EEST)
From: Mikael Johansson <mpjohans_at_pcu.helsinki.fi>
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To: Jens Spanget-Larsen <spanget_at_virgil.ruc.dk>
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Subject: Re: CCL:HOMO/LUMO gap
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Hello Jens and All!

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/