CCL: question on molecular orbitals in CO and NO

 Sent to CCL by: "Kirkpatrick, James"
 [james.kirkpatrick:+:imperial.ac.uk]
 hi,
 In my opinion, this discussion is again revolving aroung the theme of
 what does one mean by reality in science.
 "Are MOs real, or just mathematical constructs?" in my opinion
 contains
 two sides to it: a) are wavefunctions "real"
 b) are the approximations in treating the wavefunction of a molecule as
 made up of MOs appropriate.
 As regards a) I feel that most people involved in QM would say, yes MOs
 are real in the sense that very fundamental "mathematical constructs",
 such as momentum or mass or Temperature are real.
 As regards b) I imagine that it all depends on cicumstances: how are the
 MOs calculated, what system are we looking at... I imagine most people
 on this list have a better idea as to when particular model chemistries
 are appropriate and how to interpret MOs in each of those.
 So the statement "PES gives information about how MOs interact", in my
 opinion is perfectly justified, with the caveats that b) holds for the
 particular problem at hand.
 james
 -----Original Message-----
 From: Noko Phala nphala[#]angloresearch.com =
 Sent: Wed 11/30/2005 1:17 PM
 To: Kirkpatrick, James
 Subject: CCL: question on molecular orbitals in CO and NO
 Sent to CCL by: "Noko Phala" [nphala~~angloresearch.com]
 Being able to explain photoelectron spectra in terms of MO theory is not
 proof for existence of orbitals/orbital interactions. But perhaps the
 Nobel Laureate is proposing that the predictive power of the orbital
 concept so great that it is hard to not thing they are real..
 _________________________
 Dr Noko Phala
 Process Research
 Anglo Research=20
 PO Box 106 Crown Mines 2025
 Republic of South Africa
 Tel: +27 (11) 377 4817
 e-mail: nphala\a/angloresearch.com=20