1. Department of Chemical Sciences, Indian Institute of Science Education and Research, Mohanpur, Kolkata 741246, India
2. Centre for Advanced Functional Materials, Indian Institute of Science Education and Research, Mohanpur, Kolkata 741246, India
3. RIKEN-JEOL Collaboration Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan
4. JEOL RESONANCE Inc., Musashino, Akishima, Tokyo 196-8558, Japan
5. Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India