✦ LIBER ✦

Virtual orbitals

✍ Scribed by David B. Cook

Publisher: John Wiley and Sons
Year: 1996
Tongue: English
Weight: 756 KB
Volume: 60
Category: Article
ISSN: 0020-7608
DOI: 10.1002/(sici)1097-461x(1996)60:4<793::aid-qua1>3.0.co;2-s

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✦ Synopsis

It is shown that the conventional concepts based on the use of the HOMO and LUMO are founded on very questionable assumptions. In particular, it is shown both theoretically and computationally that the LUMO of almost all neutral atoms and molecules is a continuum function with energy zero. The LUMO of any SCF calculation is an artifact of the basis-expansion method. A proposal is made for the identification of the pair donor and pair acceptor orbitals which play the true role of the HOMO and LUMO.

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