Key points are not available for this paper at this time.
The molecular orientation of regioregular poly(3-hexylthiophene) varies from edge-on to plane-on depending on the film drying rate controlled by spin-coating speed. The field effect hole mobility varies accordingly. Orientation was determined with near-edge X-ray fine structure spectroscopy of the π* resonance, which is orthogonal to the conjugated plane.
DeLongchamp et al. (Thu,) studied this question.