1. Department of Physics, Florida A&M University, Tallahassee, Florida 32307, United States
2. Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russia
3. Department of Physical and Colloid Chemistry, Peoples’ Friendship University of Russia, Moscow 117198, Russia
4. Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, United States