SUMMARY
This work presents the analysis of experimental data on optical properties of viologensintroduced to the liquid crystalline medium stipulated by the application of increasing voltage values.These data along with quantum mechanical theory allowed to specify the mechanism of dimerization ofvioloden molecules which leads to the colour change of the liquid crystal-viologen sample. Specifically,the dimerization of viologen molecules in liquid crystalline medium occurs due to interaction betweenviologen molecules, which were fully reduced under the action a voltage applied, and initial viologenmolecules