1. Centre of Advanced Studies, Department of Chemistry, University of Rajasthan, Jaipur, India
2. Friedrich Schiller Univ. Jena, Inst. Anorgan. & Analyt. Chem., Humboldt Str 8, D-07743 Jena, Germany
3. Department of Physics, Arya College of Engineering and IT, Jaipur, India
4. Department of Physics, University of Rajasthan, Jaipur, India