Assessing π-Electron Contents of Rings in Polycyclic Aromatic Compounds

Polycyclic aromatic compounds ( PAC ) are a huge class of organic molecules that can be found everywhere. They called attention of scientists by their interesting and sometimes peculiar physical and chemical properties. That is why, there are a number of research articles and books in which their synthesis, properties, reactions, and theoretical investigations have been communicated. In this survey will be outlined several simple methods for assessing the partition of π-electrons in rings of some classes of PAC. Keywords: Aza-derivatives of benzenoid hydrocarbons, benzenoid hydrocarbons, electron content of a ring, electron excess, phenylenes, polycyclic aromatic compounds.