ISSN:
0192-8651
Keywords:
Computational Chemistry and Molecular Modeling
;
Biochemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Computer Science
Notes:
CNDO/S calculations are carried out on 1,3,5-cycloheptatriene (I), 1,3,5,7-cyclooctatetraene (II), all-cis-1,3,5,7-cyclononatetraene (III), and all-cis-1,4,7-cyclononatriene (IV), for which π-σ separability is a questionable matter. When disparate choices are available for the geometries, preferences are based on the agreement between calculated and experimental spectra. The microwave structure for I and an unsymmetrical conformation for III are suggested. In the electronic spectra, conjugative contributions are assigned to the lowest-energy weak band, while an ethylenic nature is to be attributed to the intense band in the range of 6 eV. The possibility of through-space π interactions is examined qualitatively. An appreciable degree of such interaction is shown by IV.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcc.540010405
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