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Updated: Jun 13, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Rotational libration of a double-decker porphyrin visualized
Joe Otsuki1, Yuji Komatsu, Daiya Kobayashi
1College of Science and Technology, Nihon University, 1-8-14 Kanda Surugadai, Chiyoda, Tokyo 101-8308, Japan. otsuki@chem.cst.nihon-u.ac.jp
Abstract:
Scanning tunneling microscopy has revealed the reorientation of one of the macrocyclic rings of the double-decker porphyrin complex [Ce(TPP-Fc)(C(22)OPP)] [TPP-Fc = 5-(4-(4-ferrocenylphenylethynyl)phenyl)-10,15,20-triphenylporphyrin; C(22)OPP = 5,10,15,20-tetrakis(4-docosyloxyphenyl)porphyrin] by 90 degrees between scans when the other ring is fixed on a surface. This libration was evidenced by monitoring the location of the appended ferrocene unit, which functioned as a molecular beacon signaling its position.
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