The McClelland number of conjugated hydrocarbons

Date

2005-12-01

Author

Gutman, I
Türker, Burhan Lemi
Furtula, B
Vuckovic, V

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The McClelland number of a conjugated hydrocarbon is the integer k, satisfying the condition 2(-(1/2)k) root 2nm <= E < 2(-(1/2)k+1) root 2nm, where E is the HMO total pi-electron energy, n the number of carbon atoms, and m the number of carbon-carbon bonds. If k = 3, then the respective conjugated system is said to be energy-regular. If k ! 2 and k ! 4, then one speaks of energy-poor and energy-rich pi-electron systems, respectively. We found that all polycyclic Kekulean hydrocarbons, possessing condensed rings, are energy-regular, with only three exceptions: naphthalene, phenanthrene, and triphenylene (which are energy-rich). Energy-poor pi-electron systems are some (but not all) non-Kekuleans, whereas many of the polycyclic Kekulean hydrocarbons with non-condensed rings (polyphenyls, phenyl-substituted polyenes and similar) are energy-rich.

Subject Keywords

Total pi-electron energy, Bounds for total pi-electron energy, McClelland number

URI

https://hdl.handle.net/11511/62869

Journal

CROATICA CHEMICA ACTA

Collections

Department of Chemistry, Article

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Citation Formats

I. Gutman, B. L. Türker, B. Furtula, and V. Vuckovic, “The McClelland number of conjugated hydrocarbons,” CROATICA CHEMICA ACTA, pp. 485–488, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62869.