1. Ghitu Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, 3/3 Akademicheskaya St., Chisinau MD-2028, Republic of Moldova and International Laboratory of High Magnetic Fields and Low Temperatures, 95 Gajowicka St., 53-421 Wroclaw, Poland
2. Department of Chemistry, Howard University, 500 College St. N.W., Washington DC 20059, USA
3. Ghitu Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, 3/3 Akademicheskaya St., Chisinau MD-2028, Republic of Moldova