High-frequency and -field EPR investigation of a manganese(III) N-confused porphyrin complex, [Mn(NCTPP)(py)2]

John D Harvey; Christopher J Ziegler; Joshua Telser; Andrew Ozarowski; J Krzystek

doi:10.1021/ic0506759

High-frequency and -field EPR investigation of a manganese(III) N-confused porphyrin complex, [Mn(NCTPP)(py)2]

Inorg Chem. 2005 Jun 27;44(13):4451-3. doi: 10.1021/ic0506759.

Authors

John D Harvey¹, Christopher J Ziegler, Joshua Telser, Andrew Ozarowski, J Krzystek

Affiliation

¹ Department of Chemistry, University of Akron, Akron, Ohio 44325, USA.

PMID: 15962946
DOI: 10.1021/ic0506759

Abstract

We report the first high-frequency and -field electron paramagnetic resonance (HFEPR) study of a Mn(III) N-confused porphyrin (NCP) complex (NCP is also known as inverted porphyrin or 2-aza-21-carbaporphyrin). We have found a striking variation in the electronic properties of the S = 2 Mn(III) ion coordinated by NCP compared to other Mn(III) porphyrinoid complexes. Thus, inversion of a single pyrrole ring greatly changes the equatorial ligand field exerted and leads to large magnitudes of both the axial and rhombic zero-field splitting [respectively, D = -3.084(3) cm(-1), E = -0.608(3) cm(-1)], which are unprecedented in other Mn(III) porphyrinoids.