1. STAR Laboratory, Department of Chemistry, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Anantapur, Andhra Pradesh 515134, India
2. Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
3. Department of Chemistry, Indian Institute of Technology, Gandhinagar 382355, India