The structure dependence of the total π-electron energy E (and therefore of the thermodynamic stability) of phenylenes is examined. Sharp and narrow upper and lower bounds for E are obtained. The gross part of E (above 99%) is determined by the size of the phenylene molecule, measured by the number h of hexagons. An approximate mathematical form of the dependence of E on h is established.
- Chemical graph theory
- Total π-electron energy