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Updated: Oct 1, 2025

Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Electrochemically Driven Swinging of a Nitrobenzyl Pendant Arm in a Nickel Scorpionand Complex
Carlo Ciarrocchi1, Luigi Fabbrizzi1, Maurizio Licchelli1
1Dipartimento di Chimica, Università di Pavia, 27100, Pavia, Italy.
Abstract:
A radical anion -NO2 .- is formed upon an electrochemically reversible one-electron reduction of the square-planar NiII complex of N-nitrobenzylcyclam. The -NO2 .- group goes to occupy an axial position of the metal ion, thus establishing a significant electronic interaction with the metal center. In particular, the ESR spectrum supports the occurrence of an electron transfer from -NO2 .- to the metal, which therefore presents a significant NiI character. On re-oxidation, the nitrobenzyl side chain detaches and the NiII complex is restored, providing an example of a fully reversible redox driven intramolecular motion.
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