ИСТИНА

A molecular-statistical theory describing the nematic LC with point (spherical) defects is derived. The nematic order parameters and the elastic constants are evaluated in the framework of a unified approach based on the features of pair interaction potentials of the individual liquid crystal molecules. We demonstrated that the nematic order is completely destroyed in the bulk in the abnormal case K33<K11 due to the presence of point defects (see Fig. 1); Therefore we have probably shown why K33 is always larger than K11 in nematics. We explain the two-step heat-driven transformation from the nematic phase with point defects embedded with spherical nanoparticles into the isotropic phase.  We have shown that, in contrast to the case of flat surfaces [1,2], the transition from nematic phase to the isotropic phase near the strongly distorted surface (the first step) happens at lower temperatures than the transition in the bulk of a liquid crystal (the second step).