title: Theoretical studies on the structures and strain energies of cycloparaphenylenes.
abstract: The structures and strain energies of cycloparaphenylenes (CPPs) have been determined by DFT calculation at the B3LYP/6-31G(d) level of theory. Fifteen stable conformations of [12]CPP were found as local minimum structures. It was also found that benzene rings of [12]CPP can rotate rather freely at room temperature. The strain energies of [n]CPP (n = 6-20) were estimated on the basis of the homodesmotic reaction using CPP, biphenyl, and p-terphenyl. It was also found that CPPs have higher strain energy in comparison to cycloparaphenyleneacetylenes (CPPAs).
authors.affiliation: Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Segawa
authors.forename: Haruka
authors.initials: H
authors.lastname: Omachi
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Itami
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D003198:Computer Simulation; D008956:Models, Chemical; D015394:Molecular Structure; D013816:Thermodynamics
chemical_list: D001555:Benzene Derivatives