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Updated: Jul 9, 2026

Preparation and Characterization of C60/Graphene Hybrid Nanostructures
Published on: May 15, 2018
Open-shell singlet character of cyclacenes and short zigzag nanotubes
Zhongfang Chen1, De-en Jiang, Xin Lu
1Department of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, USA. chen@chem.uga.edu
Abstract:
The electronic ground states of [n]cyclacenes, as well as short-zigzag nanotubes, computed at unrestricted broken spin-symmetry density functional theory (UBS-DFT), were found to be open-shell singlets, rather than triplets. Computations for [6]cyclacene at complete active space self-consistent field (CASSCF) and multireference perturbation theory (MRMP2) levels support this conclusion. Along with strain, the radical character of the open-shell singlet with antiferromagnetically coupled electron spins may contribute to the difficulties in synthesizing [n]cyclacenes.
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