1. a Section of Solid State Physics, Department of Physics , University of Athens , Panepistimiopolis, Zografos , 157 84 , Greece
2. b Laboratory of Organic Chemistry, Department of Chemical Engineering , National Technical University of Athens , Zografou Campus, 15 773 , Greece
3. c Laboratory of Inorganic Chemistry, Department of Chemistry , University of Athens , Panepistimiopolis, 15 771 , Greece