1. Department of Chemistry, Babes-Bolyai University, Cluj-Napoca, RO-400028, Romania
2. Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
3. Research Centre for Crystalline Materials, Faculty of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia