ISSN:
1572-9540
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract In order to study structural influences on the interaction of Fe(IV) (S=1) and porphyrin cation radical (S′=1/2) in high-valent iron porphyrin complexes of the type ¦X-(TMP)Fe=O¦+(Cl−), X=I, Br2, Br4 were generated by mCPBA oxidation of corresponding Fe(III) porphyrins. The halogen substitution at the peripheral positions of the porphyrin leads to distortion of the planar porphyrin ring of ¦(TMP)Fe=O¦+. The new species have beeen investigated by temperature-dependent EPR and field-dependent Mössbauer spectroscopy; for the evaluation of spectra, we adopted the spin-Hamiltonian formalism including exchange interaction explicitly. As in ¦(TMP)Fe=O¦+, strong ferromagnetic spin coupling was observed with|J0|D=0.9–1 and a zero-field spltting ofD∼32 cm−1. For consistent parametrization of EPR and Mössbauer results, anisotropic coupling had to be introduced. Compared to ¦(TMP)Fe=O¦+ [1], analysis of the spectroscopic data shows that zero-field splitting and spin coupling is only slightly affected by the halogen distortion of the porphyrin structure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02064610
