Author/Authors :
Poplawski، نويسنده , , J. and Ehrenfreund، نويسنده , , E. and Cornil، نويسنده , , J. L. Brédas and W. R. Salaneck، نويسنده , , J.L. and Pugh، نويسنده , , R. and Ibrahim، نويسنده , , M. and Frank، نويسنده , , A.J.، نويسنده ,
Abstract :
We present studies of neutral films of sexithiophene (6T) using the photoinduced absorption spectroscopy technique. We find two strong absorption bands very similar in energy (0.80 and 1.54 eV) and shape (both feature shoulders) to those found for the radical cation 6T∗+. In addition, there is a weak band (at 1.1 eV) similar in energy to that of the dication related band (1.2 eV for 6T++). Measurements of the modulation frequency and temperature dependence of the photogenerated defects show that the main long lived nonlinear excitations are polarons (radical cations.)
