1. Eduard-Zintl-Institute
for Inorganic Chemistry and Physical Chemistry, Technical University Darmstadt, Alarich-Weiss-Straße 8, D-64287 Darmstadt, Germany
2. Institut
für Materialwissenschaft, Technische Universität Darmstadt, Jovanka-Bontschits-Straße 2, D-64287 Darmstadt, Germany
3. Institute
for Physical and Theoretical Chemistry, University Frankfurt, Max-von-Laue-Straße7, 60438 Frankfurt, Germany
4. Institute
of Coal Chemistry, Chinese Academy of Sciences, South Taoyuan Road 27, 030001 Taiyuan, P.R.China
5. Department
of Materials and Earth Sciences, Technical University Darmstadt, Alarich-Weiss-Straße 2, D-64287 Darmstadt, Germany