Laser-Laboratorium Göttingen e.V.

Laser-Laboratorium Göttingen e.V.

Frank de Groot: X-ray spectroscopy of transition metal oxides

Termin: 01. November 2016 um 10:00h im Seminarraum

Veranstaltungsort: Laser-Laboratorium Göttingen e.V., Hans-Adolf-Krebs-Weg 1, 37077 Göttingen

„X-ray spectroscopy of transition metal oxides“
New developments in x-ray absorption (XAS) and resonant inelastic x-ray scattering (RIXS) applied to transition metal oxides will be discussed. A brief introduction is given of x-ray spectroscopy, including the multiplet interpretation of XAS and RIXS spectral shapes [1,2]. Soft x-ray absorption microscopy can be performed with 10 nm resolution under ambient conditions [3]. In 2p3d RIXS one scans through the 2p XAS edge and measures the optical excitation range. As an example, the RIXS spectra of cobalt systems will be discussed. The experimental resolution of sub-100 meV allows the detailed observation of the electronic and magnetic structure. First-principle theoretical modelling was performed for the ground state and multiplet analysis for the RIXS experiments. The implications for measurements on coordination compounds and nanoparticles are discussed, in particular the comparison with optical spectroscopy [4].

[1] Core Level Spectroscopy of Solids. Frank de Groot and Akio Kotani (Taylor & Francis CRC press, 2008)
[2] Download the x-ray spectroscopy simulation software at www.anorg.chem.uu.nl/CTM4XAS/ 
[3] E. de Smit et al. Nature 456, 222 (2008). 
[4] M. van Schooneveld et al. Angew. Chem. 52, 1170 (2012)


Frank de Groot is an associate professor in the department of chemistry at Utrecht University. His work reflects a concern with both the theoretical and experimental aspects of x-ray spectroscopy. His current interest is in the use of x-ray spectroscopies for the study of the electronic and magnetic structure of condensed matter, in particular for transition metal oxides, (magnetic) nanoparticles and heterogeneous catalysts under working conditions.