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Updated: Aug 15, 2025

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
An exchange coupled meso-meso linked vanadyl porphyrin dimer for quantum information processing
Davide Ranieri1, Fabio Santanni1, Alberto Privitera1
1Department of Chemistry "Ugo Schiff" & INSTM RU, University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy lorenzo.sorace@unifi.it.
Abstract:
We report here the synthesis of a new meso-meso (m-m) singly linked vanadyl-porphyrin dimer that crystallizes in two different pseudo-polymorphs. The single crystal continuous-wave electron paramagnetic resonance investigation evidences a small but crucial isotropic exchange interaction, J, between the two tilted, and thus distinguishable, spin centers of the order of 10-2 cm-1. The experimental and DFT studies evidence a correlation between J values and porphyrin plane tilting angle and distortion. Pulsed EPR analysis shows that the two vanadyl dimers maintain the coherence time of the monomer. With the obtained spin Hamiltonian parameters, we identify suitable transitions that could be used as computational basis states. Our results, coupled with the evaporability of porphyrin systems, establish this class of dimers as extremely promising for quantum information processing applications.
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