Influence of Electric Fields on the Molecular Alignment in the Liquid-Crystal para-Azoxyanisole

Abstract

The molecular alignment in the liquid crystal p‐azoxyanisole due to external static magnetic fields and audio‐frequency electric fields was studied by measuring the dielectric loss at a microwave frequency. For a 500‐Hz electric field the long axes of the molecules preferred a direction parallel to the field which is usually observed but not predicted from theoretical considerations. The degree of alignment in a high 500‐Hz electric field was less than in a high magnetic field and depended on the frequency of the electric field. The effectiveness of electric fields in aligning the molecules was compared to that of magnetic fields by applying the fields simultaneously and at right angles to each other. The results provide support for an explanation of the molecular alignment at audio frequencies, which was suggested earlier by one of the authors.