1. Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
2. Umicore AG & Co. KG, Rodenbacher Chaussee 4, 63457 Hanau, Germany
3. Center of Materials Research, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
4. Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
5. Institute of Theoretical Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany