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Updated: Jul 15, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Spin-localized cyclopentadienyl radical annelated with homoadamantene frameworks: isolation, X-ray crystal structure,
Toshikazu Kitagawa1, Kohei Ogawa, Koichi Komatsu
1Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan. kitagawa@scl.kyoto-u.ac.jp
Abstract:
A cyclopentadienyl radical annelated with two homoadamantene frameworks 1 was synthesized and isolated in stable, crystalline form by the single-electron oxidation of the corresponding cyclopentadienyl anion. The X-ray structure clearly demonstrated distinct bond alternation in the cyclopentadienyl ring, suggesting that radical 1 has the characteristics of a spin-localized 2,4-cyclopentadien-1-yl radical. The two homoadamantene frameworks are nonequivalent in crystals at 100 K, while ESR spectra indicated that they are equivalent in toluene at room temperature due to rapid changes in conformation.
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