Berlin 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MO: Fachverband Molekülphysik

MO 8: Electronic Spectroscopy 1

MO 8.5: Vortrag

Dienstag, 18. März 2014, 15:15–15:30, BEBEL HS213

The effect of ligand field symmetry on charge transfer process: x-ray absorption and emission investigation on Fe L edge of iron porphyrins — •Marvin Pohl, Jie Xiao, Ronny Golnak, Kaan Atak, Christoph Schwanke, Edlira Suljoti, and Emad Aziz — Department of Functional Materials in Solution, BESSY II, Helmholtz Zentrum Berlin, Germany

Iron porphyrin is the central and functional part existing in many vital proteins in biological system. The iron ion is the actual active site catalyzing a variety of complicated chemical reactions in which the iron 3d orbitals are strongly involved. Soft X-ray spectroscopy is an ideal tool to probe local electronic structure, which has recently been implemented by our team for the investigation of applied materials in liquid phase. Two iron porphyrin complexes with different side groups, iron octaethylporphyrin chloride (FeOEPCl) and iron tetraphenylporphyrin chloride (FeTPPCl), dissolved in solvent dichloromethane (CH2Cl2) have been investigated in flow cell by x-ray absorption and emission spectroscopy on Fe L edge. Their liquid phase resembles the real situation in biological system. The different delocalization extents of the certain Fe 3d orbital over the ligand N atoms under the x-ray excitation were revealed in the XAS and XES spectra of the two porphyrin molecules. The respective ligand field symmetry was found responsible for the various Fe 3d orbital overlapping with the ligand N 2p orbital in these two molecules which plays a significant role in the charge transfer process.