Macromolecules, Vol.40, No.10, 3610-3614, 2007
Evidence for 21-helicity of poly[9,9-bis(2-ethylhexyl)fluorene-2,7-diyl]
The conformational state of the pi-conjugated polyfluorene poly[9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] is reconsidered. Contrary to the general opinion, this helical polymer is shown to organize in a giant repeat consisting of 21 monomer units. The length of the unit cell of 16.97 nm is suggested.