ROLE OF THE PERMANENT QUADRUPOLE-MOMENT OF A DISPERSED PARTICLE IN ELECTROORIENTATION

The electroorientation effect of the second order on the field is not exhausted by the interaction of the field with the induced dipole mome nt of the particle. An alternative is the interaction of the equilibri um quadrupole moment of the particle with a polarization electric fiel d, which in the second approximation on the field E has a quadrupole s ymmetry with respect to the direction of E and the center of the parti cle. The traditional component of electroorientation is missing in the isopolarization state (when the dipole moment of the particle is equa l to zero). The alternative component, which we have detected and inve stigated, is missing in the isoelectric state (when the surface of the particle at equilibrium is not charged). The ratio of the new and the known effects has been investigated for a spheroid in the limiting ca se of a thick (in comparison with the linear dimensions of the particl e) electrical double layer at the interface between the phases for a l arge number of parameters of the dispersed system.