1. Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
2. Dipartimento di Medicina, Chirurgia e Farmacia, Viale San Pietro, Università di Sassari, Sassari I-07100, Italy
3. Departamento de Química Inorgánica, Universidad de Valencia, C/Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
4. Department of Chemistry, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan