1. Department of Chemistry, Karnatak University, Dharwad 580003, India
2. Department of Physics, Laser Spectroscopy (DRDO/KU) Programme, Karnatak University, 580003, Dharwad, India
3. Dr Prabhakar Kore Basic Science Research Centre, KLE Academy of Higher Education and Research (KLE University), 590010, Belagavi, India