title: Fine-Tuning of Electronic Structure of Cobalt(II) Ion in Nonplanar Porphyrins and Tracking of a Cross-Hybrid Stage: Implications for the Distortion of Natural Tetrapyrrole Macrocycles.
abstract: The core size of the porphyrin macrocycles was closely related to their stability of the different electron structure in the central metal ion. Cobalt(II) ions can undergo a conversion in electron configurations upon N4 core contraction of 0.05 Å in nonplanar porphyrins, and these ions still maintain low spin forms after and before conversion. The structural fine-tuning can induce the appearance of a cross-hybrid stage [d(x(2)-y(2))sp(2) ↔ d(z(2))sp(2)] based on quadrilateral coordination of the planar core. The results indicate that the configuration conversion plays a key role in electron transfer in redox catalysis involving cobalt complexes. The electronic properties of six monostrapped cobalt(II) porphyrins were investigated by spectral, paramagnetic, and electrochemical methods. The macrocyclic deformations and size parameters of Co-containing model compounds were directly obtained from their crystal structures.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.|Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology , Xiangtan 411201, China.
authors.forename: Qiuhua
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology , Xiangtan 411201, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology , Xiangtan 411201, China.
authors.forename: Wennan
authors.initials: W
authors.lastname: Zeng
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha 410083, China.
authors.forename: Jianxiu
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology , Xiangtan 411201, China.
authors.forename: Zaichun
authors.initials: Z
authors.lastname: Zhou