- Tytuł:
- Spectroscopic Study of the Dimerization Process οf Iron Protoporphyrin IX
- Autorzy:
-
Dziedzic-Kocurek, K.
Byrne, H.
Świderski, A.
Stanek, J. - Tematy:
-
36.20.-r
36.20.Kd
36.20.Ng - Pokaż więcej
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Powiązania:
- https://bibliotekanauki.pl/articles/1809653.pdf Link otwiera się w nowym oknie
- Opis:
- The commercial protoporphyrin IX, iron-ferriprotoporphyrin IX-chloride and synthesized iron porphyrin μ-oxo-dimers were examined by UV/vis absorption and fluorescence, Fourier transformed infrared spectroscopy, resonance Raman, X-ray absorption, Mössbauer spectroscopy and SQUID. The evidence of Fe-O-Fe antiferromagnetic coupling concluded from SQUID and Mössbauer in the case of samples containing dimerized forms confirmed the presence of the oxo-bridges. In this paper the results of UV/vis, fluorescence, Fourier transform infrared FTIR and Raman spectroscopies are reported and discussed. The study is based on the comparison of the free-base protoporphyrin IX, Fe-PPIX-Cl and the synthesized dimerized specimen. The vibrational modes in two energy regions i.e. 330-650 $cm^{-1}$ and 750-900 $cm^{-1}$, reportedly characteristic of the existence of Fe-O-Fe bridges, are discussed. A significant photoluminescence emission, strongly Stokes shifted from the Soret band, absent in the protoporphyrin IX and the iron-ferriprotoporphyrin IX-chloride, is observed. The strong Stokes shift and the mismatch of the excitation spectrum to the Soret band suggest that is does not have origin in the de-excitation of the porphyrin moiety and that it could have origin in an Fe-O-Fe charge transfer state.
- Dostawca treści:
- Biblioteka Nauki
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