title: On the stability of large [4n]annulenes.
abstract: [reaction: see text] The stabilization energies (B3LYP/6-31G) of planar [4n]annulenes, evaluated by a new indene-isoindene isomerization method (see Abstract graphic), reveal that all 4n pi-electron rings larger than the energetically unfavorable cyclobutadiene are only slightly destabilized by the pi-electron interactions. Cyclooctatetraene prefers the "tub" conformation because of strain effects. Generally, the antiaromatic character of the larger systems with 4n pi-electrons is revealed best by their magnetic properties rather than by their energies.
authors.affiliation: [reaction: see text] Computational Chemistry Annex, Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Chaitanya S
authors.initials: CS
authors.lastname: Wannere
authors.forename: Damian
authors.initials: D
authors.lastname: Moran
authors.forename: Norman L
authors.initials: NL
authors.lastname: Allinger
authors.forename: B Andes
authors.initials: BA
authors.lastname: Hess
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Schaad
authors.forename: Paul von Ragué
authors.initials: Pv
authors.lastname: Schleyer