Orientational ordering process of 4′-n-pentyl-4-cyanobiphenyl molecules deposited on polyimide Langmuir–Blodgett films

The orientational ordering processes of 4′-n-pentyl-4-cyanobiphenyl (5CB) molecules on Kapton-type polyimide Langmuir–Blodgett (LB) films were experimentally examined. During 5CB deposition, in situ observation was conducted and the orientational order of 5CB molecules was determined in terms of orientational order parameters Sn (n = 1, 2, 3) using optical second-harmonic generation (SHG) and optical polarized absorption (PA) measurements. Experimental data were discussed in connection with anchoring energy dependence on the number of polyimide layers.