Croatica Chemica Acta, Vol. 86 No. 4, 2013.
Original scientific paper
https://doi.org/10.5562/cca2291
An Analysis of Topological Ring-Currents and their Use in Assessing the Annulene-Within-an-Annulene Model for Super-Ring Conjugated Systems
T. K. Dickens
; University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, England, United Kingdom
R. B. Mallion
; School of Physical Sciences, University of Kent, Canterbury CT2 7NH, England, United Kingdom
Abstract
The Hückel–London–Pople–McWeeny approach to calculating ring currents in conjugated
systems is considered in detail, especially the ‘topological’ variant of this formalism, particularly emphasised
during the last five years. A step-by-step account is given of how these calculations are effected in
practice, in such a way as to enable any interested reader to carry out these computations himself. The
method is illustrated by using it to assess the applicability of the so-called ‘Annulene-Within-an-Annulene
(AWA) Rule’ to ‘super-ring’ conjugated hydrocarbons — some in which the inner ring and outer perimeter
are ‘coupled’, and others in which they are ‘decoupled’. Compliance with the AWA model appears
more probable in decoupled super-ring structures than in coupled ones. The Appendix touches on previous
work involving Professor D. J. Klein, the honorand of this issue. (doi: 10.5562/cca2291)
Keywords
topological ring-currents and bond-currents; graph theory; conjugated hydrocarbons; coupled and decoupled super-ring systems; annulene-within-an-annulene rule
Hrčak ID:
112761
URI
Publication date:
16.12.2013.
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