1. Institute of Solid State Physics, Graz University of Technology, 8010 Graz, Austria
2. Chair for Theoretical Chemistry and Catalysis Research Center, Technical University Munich, 85748 Garching, Germany
3. Chair for Theoretical Physics VII and Bavarian Center for Battery Technology (BayBatt), University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany