[1] Univ Pardubice, Fac Chem Technol, Dept Phys Chem, Studentska 573, Pardubice 532 10, Czech Republic
[2] Univ Pardubice, Fac Chem Technol, Ctr Mat & Nanotechnol CEMNAT, Nam Cs legii 565, Pardubice 530 02, Czech Republic
[3] Herzen State Pedag Univ Russia, Inst Phys, Dept Phys Elect, 48 Moika Emb, St Petersburg 191186, Russia