Conversion of electron configuration of iron ion through core contraction of porphyrin: implications for heme distortion
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Updated: May 15, 2026

Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
Zaichun Zhou1, Qiuhua Liu, Ziqiang Yan
1School of Chemistry and Chemical Engineering, and Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education, Hunan University of Science and Technology, Xiangtan 411201, China. zhouzaichun@hnust.edu.cn
Abstract:
It was demonstrated experimentally that nonplanar iron porphyrins can be induced to undergo a conversion in their electronic configuration to form a cross-hybrid transition by compressing the macrocyclic core size for the central metal ion. A series of monostrapped iron porphyrins were used as model systems, and their electronic properties were probed using electron spin resonance and differential spectral analyses. These results indicate that the formation of a cross-hybrid transition stage is related to the stability of the high-valence state and potent oxidizing ability of the central iron ion.
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