CONFINEMENT EFFECT IN A THICK LAYER OF NEMATIC LANTHANIDE COMPLEX

The structure of metallomesogens complexes differs essentially from that of calamitic liquid crystals that emerges in their physical properties. We studied anomalous features of the transition from nematic to isotropic phase (N-I) in the ytterbium-based liquid crystal complex. For this, two approaches were used.  At first approach, we showed that the experimental values of the dielectric and optical anisotropies measured near the phase transition turned out to be substantially smaller than their calculated values. This is evidently taken place because the phase transition temperature in the deep of the experimental cell differs from that near the surface of the cell. Secondly, the temperature of N-I transitions in metallomesogenic layers being within glass sandwich cells is obtained directly by means of the polarization microscope method. It was found that the phase transition temperature drops in more than ten degrees when reducing of metallomesogenic layer thick form 200 to 5 microns. The calamite liquid crystals show the confinement effect only within interstice of the specific size smaller than one micron. An anomalous confinement effect can be caused by a strong interaction of the complexes with each other.