1. Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, 06269-3060, United States
2. U.S.
Department of Energy, Ames Laboratory, Ames, Iowa 50011-3020, United States
3. Department
of Chemistry, Iowa State University, Ames, Iowa 50011-3111, United States
4. School
of Pure and Applied Science, Department of Physical Science, South Eastern Kenya University, P.O. Box 170-90200, Kitui 90200, Kenya