1. Manonmaniam Sundaranar University, Abishekapatti, Tirunelveli, Tamil Nadu, India
2. Department of Physics, Research Centre, Nesamony Memorial Christian College, Marthandam, Tamil Nadu, India
3. Department of Chemistry, NSS College Ottapalam, Palakad, Kerala, India
4. Centre for Molecular and Biophysics Research, Department of Physics, Mar Ivanios College, Thiruvanathapuram, Kerala, India