抄録
We have studied second harmonic generation(SHG) in both crystalline and nematic phases of aromatic copolyester of 4-hydroxy benzoic acid(HBA) and 6-hydroxy-2-naphthoic acid(HNA). The SH profiles as a function of incident or SH polarizations are well similated under the model of C3 symmetry with a mirror plane rotationally disordered about the molecular long axis. This is the first polar, probably ferroelectric liquid crystal.
