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Updated: Dec 31, 2025

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Intermolecular Interactions and Intramolecular Couplings of Binuclear Porphyrin Models for Cytochrome c Oxidase
Zhen Yao, Charles E Schulz1, Jiahui Yang2
1Department of Physics , Knox College , Galesburg , Illinois 61401 , United States.
Abstract:
Cytochrome c oxidase (CcO) has a binuclear active site composed of a high-spin heme group and a tris-histidine-ligated copper ion (CuB). By using two different porphyrin models derived by Gunter (H2TPyPP) and us (H2TImPP), we have isolated several mono- and binuclear complexes including one carbonyl and three chloride derivatives which are determined by 100 K single-crystal X-ray. Low-temperature (4 K) EPR and multitemperature (295-25 K) Mössbauer investigations on the products not only confirmed the spin states of the two metal ions (S = 5/2 Fe3+ and S = 1/2 Cu2+) but also revealed the intermolecular interactions and intramolecular couplings which are in accordance with the crystal structural features.
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