Why are the kinked polyacenes more stable than the straight ones? A topological study and introduction of a new topological index of aromaticity.
A topological model for estimating the stability of benzenoid hydrocarbons (BHs) is presented showing an acceptable linear dependence on Hess-Schaad resonance energy per pi-electron values. The topological measure of stability is accessible by use of pencil calculation and is based on counting cis-type fragments of double bonds in all canonical structures of a given BH. Evidence is given that infinite chains of straight linear polyacenes are always less stable than the kinked ones.
Institute of Biochemistry and Biophysics, Polish Academy of Science, Pawinskiego 5a, 02-106 Warsaw, Poland. arcad@ibb.waw.pl
Arkadiusz
A
Ciesielski
Tadeusz M
TM
Krygowski
Michał K
MK
Cyrański
D015394:Molecular Structure; D011083:Polycyclic Compounds / Q000737:chemistry*
D011083:Polycyclic Compounds