ISSN:
0020-7608
Schlagwort(e):
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The Woodward-Hoffmann (WH) Rules for the prediction of relative rates and stereochemistry of concerted reactions are based on considerations of the orbital symmetry of the reactants and products. Literally hundreds of reactions have been successfully categorized by these remarkably simple-appearing Rules. This paper develops a one-dimensional band model of these Rules. By explicit inclusion of the effects of an electromagnetic field in a standard gauge-invariant fashion, it can be shown that at certain levels of field strength the model suggests that the Rules may be reversed. This is because the Rules appear in the model as a consequence of a centrifugal angular momentum barrier that can be shifted by an electromagnetic field. This barrier could account for “aromatic” stabilization. As an additional effect, the model predicts flux-dependent oscillations and persistent currents for “aromatic” molecules due to the Aharonov-Bohm effect. The possible health effects of electromagnetic fields are speculated. The likelihood of experimental observations to verify the applicability of the model is discussed.
Zusätzliches Material:
13 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/qua.560430404
Permalink
