1. Department of Chemistry, College of Science, Sultan Qaboos University, P.O. Box 36, Al-Khod 123, Muscat, Sultanate of Oman, Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom, Department of Chemistry and Open Research Center for Molecule-Based Devices, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Japan, and School of Physics, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, South Africa