1. Department of Physics, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa
2. Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, SE412 96, Sweden
3. Department of Chemistry, Addis Ababa University, Addis Ababa, 33658, Ethiopia
4. Department of Physics, Addis Ababa University, Addis Ababa, 1176, Ethiopia
5. National Institute for Theoretical and Computational Sciences (NITheCS), South Africa