1. Department of Physics and Mathematics, University of Hull, Hull HU6 7RX, United Kingdom
2. Physics Department, College of Science, University of Baghdad, Baghdad 10071, Iraq
3. Department of Inorganic Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology, 812 37 Bratislava, Slovakia
4. School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
5. Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
6. Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic