1. Polymer Science Unit
2. Indian Association for the Cultivation of Science
3. Kolkata-700032
4. India
5. Max Planck Research Group for Organic Optoelectronics
6. Max Planck Institute for Polymer Research
7. D-55128 Mainz
8. Germany
9. Institut für Organische Chemie and Center for Nanosystems Chemistry
10. Universität Würzburg
11. 97074 Würzburg