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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Theoretical studies on the structures and strain energies of cycloparaphenylenes
Yasutomo Segawa1, Haruka Omachi, Kenichiro Itami
1Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
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).
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