Microspectroscopic Analysis of the X-Ray-induced Photoreduction in Fe- and Mn-containing SMMs

作者：Schmidt Norman; Scheurer Andreas; Sperner Stefan; Fink Rainer H^*

来源：Zeitschrift fur Naturforschung Section B-A Journal of Chemical Sciences, 2010, 65(3): 390-398.

• Single-molecule Magnet (SMM)
• X-Ray Absorption
• X-Ray Microspectroscopy
• STXM
• Photoreduction

Scanning transmission X-ray microspectroscopy (STXM) and L-edge near-edge X-ray absorption tine structure (NEXAFS) spectroscopy have been applied to study the valence states of metal ions in various Fe- and Mn-containing single-molecule magnet materials, in particular the ligand-stabilized metal complexes NaFe(6) (so-called "ferric wheel"), Fe(4) (so-called "ferric star") and Mn(7) (so-called "manganese wheel"). We compare dose-dependent L-edge absorption spectra with the results of theoretical studies of the involved metal ions to conclude on the change in oxidation state upon increasing the X-ray dose. It is found that even low-intensity irradiation induces the reduction of the weakly interacting metal ions, and that the soft X-ray-induced photoreduction is less pronounced in microcrystalline films.

• 出版日期2010-3