Original scientific paper

Definition of Aromaticity on the Basis of Molecular Orbital Localizability

G. Naray-Szabo ; Chinoin Pharmaceutical and Chemical Works Ltd. H-1325 Budapest, Hungary
K. Horvath ; Chinoin Pharmaceutical and Chemical Works Ltd. H-1325 Budapest, Hungary

Abstract

A new quantitative measure is given to characterize the aromaticity
of conjugated molecules. By definition the aromaticity
index, A, is equal to the deviation from the unity of the average
it-orbital localizability of the molecule. The localizability of molecular
orbitals is defined according to Diner, Malrieu, Jordan and
Claverie. Aromaticity indices were calculated for 21 homo- and
heteroconjugated molecules using the CND0/2 method. The relationship
between our index and some other ones is discussed. In addition,
the role of d-orbitals in aromaticity and the relation of
Hiickel's 4n + 2 rule to our definition are analyzed.

Keywords

Hrčak ID:

196341

URI

https://hrcak.srce.hr/196341

Publication date:

20.7.1977.

Visits: 588 *