The synthesis of molecules consisting of various combinations of phenylene and thiophene groups and the subsequent vacuum growth of needle-shaped nanoaggregates on specific surfaces allows us a systematic investigation of the transition between single parallel and multiple aligned needle ('nanofiber') growth. The former growth mode is observed for blue light emitting phenylene fibers, whereas the latter growth mode appears for single crystalline fibers made from green- and orange-light emitting oligo-thiophenes and thiophene/phenylene co-oligomers. In all cases the tailored bottom-up growth results in strongly polarized light emission along specific surface directions. The results are compared to those found for nanoaggregates made from less rod-like organic molecules, namely rubrene and POPOP.

Date Published: 7 February 2007
PDF: 11 pages
Proc. SPIE 6470, Organic Photonic Materials and Devices IX, 647006 (7 February 2007); doi: 10.1117/12.700043

Published in SPIE Proceedings Vol. 6470:
Organic Photonic Materials and Devices IX
James G. Grote; Francois Kajzar; Nakjoong Kim, Editor(s)