Details

Autor(en) / Beteiligte

• Kuepper, Karsten
• Derks, Christine
• Taubitz, Christian
• Prinz, Manuel
• Joly, Loc
• Kappler, Jean-Paul
• Postnikov, Andrei
• Yang, Wanli
• Kuznetsova, Tatyana V
• Wiedwald, Ulf
• Ziemann, Paul
• Neumann, Manfred

Titel

Electronic structure and soft-X-ray-induced photoreduction studies of iron-based magnetic polyoxometalates of type {(M)M5}12FeIII30 (M = MoVI, WVI)

Ist Teil von

• Dalton transactions : an international journal of inorganic chemistry, 2013, Vol.42 (22), p.7924-7935

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Giant Keplerate-type molecules with a {Mo 72 Fe 30 } core show a number of very interesting properties, making them particularly promising for various applications. So far, only limited data on the electronic structure of these molecules from X-ray spectra and electronic structure calculations have been available. Here we present a combined electronic and magnetic structure study of three Keplerate-type nanospherestwo with a {Mo 72 Fe 30 } core and one with a {W 72 Fe 30 } core by means of X-ray absorption spectroscopy, X-ray magnetic circular dichroism (XMCD), SQUID magnetometry, and complementary theoretical approaches. Furthermore, we present detailed studies of the Fe 3+ -to-Fe 2+ photoreduction process, which is induced under soft X-ray radiation in these molecules. We observe that the photoreduction rate greatly depends on the ligand structure surrounding the Fe ions, with negatively charged ligands leading to a dramatically reduced photoreduction rate. This opens the possibility of tailoring such polyoxometalates by X-ray spectroscopic studies and also for potential applications in the field of X-ray induced photochemistry. This work describes the electronic and magnetic properties of iron-based polyoxometalates.