| Numéro |
J. Phys. Colloques
Volume 47, Numéro C8, Décembre 1986
EXAFS and Near Edge Structure IV
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|---|---|---|
| Page(s) | C8-653 - C8-657 | |
| DOI | https://doi.org/10.1051/jphyscol:19868124 | |
J. Phys. Colloques 47 (1986) C8-653-C8-657
DOI: 10.1051/jphyscol:19868124
OBSERVATION OF IN SITU FORMATION OF PHTHALOCYANINE-BIS (PYRIDINE) IRON(II) BY X-RAY ABSORPTION SPECTROSCOPY
K.-H. FRANK1, E.-E. KOCH1 et H.-W. BIESTER21 Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-1000 Berlin 33, F.R.G.
2 II. Institut für Experimentalphysik, Universität Hamburg, D-2000 Hamburg 50, F.R.G.
Abstract
X-ray absorption spectroscopy has been employed to study in situ the changes in the local structure of the central atom of Fe-Phthalocyanine (FePC) by the adsorption of pyridine. A dipole-forbidden (1s→3d) pre-edge structure of the Fe K-edge has been observed which indicates the D4h symmetry of FePC. This 1s→3d transition is missing in the spectrum of the FePC-pyridine complex. The disappearance of the pre-edge structure is interpreted by the adsorption of two pyridine molecules to the FePC molecular plane leading to a change of the fourfold symmetry into an octahedral geometry. The absence, of a chemical shift of the Fe K-edge indicates that the complex has been formed without a net transfer of electron charge between the central atom and the pyridine ligands.