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A new method for determination of rheological parameters of liquid crystals with zero anisotropy of diamagnetic susceptibility is proposed, which is based on the measurement of the quadrupole splitting line of the NMR 2 H spectrum. The method provides higher information content of the experiments, with the shear flow discarded from consideration, compared to that obtained by the classical Leslie-Ericksen theory. A comparison with the experiment is performed, the coefficients of anisotropic viscosity of lecithin/D 2 O/cyclohexane are determined, and a conclusion is drawn as concerns the domain shapes.The liquid-crystal state of matter is appealing to investigators for two reasons: due to high optical sensitivity of liquid crystals to electric field variation under negligibly low voltage and low consumed power, and due to a striking variety of physical effects in liquid crystals, being a consequence of their structural arrangement. It is their viscosity that controls running speed of LC devices. It is therefore very critical to determine the value of viscosity factors of liquid crystals.Currently, there is a great variety of techniques that allow determining rheological parameters of anisotropic liquids. For instance, using rotary or capillary viscometers one can measure the dynamic and kinematic viscosity, the method of ultrasonic shear provides for determination of the value of dynamic viscosity, the examination of the Poiseuille or Couette flow makes it possible to find the Mesovich viscosity coefficients, etc.A tendency to form liquid-crystal phases is inherent in those substances whose molecules have shape anisotropy, similarly to rods or discs. A distinguishing feature of liquid-crystal states is a tendency of molecular axes to arrange along the common axis referred to as director. Being in a constant magnetic field, the director is adjusted primarily along the filed lines. For specimens with zero anisotropy of diamagnetic susceptibility, adjustment of the director could be achieved by superposition of shear flow. Upon disruption of the shear flow, the specimen's domain gets to be misoriented, the mean ordering parameter is decreased and so is the mean quadrupole splitting of lines of the NMR spectrum. Using experiments, one can determine the dependence of the ordering parameter value and that of the mean splitting of the NMR spectrum of the specimen on time.We constructed our models according to the classical Leslie-Ericksen-Parody theory [1,2]. Its disadvantage is that it appears impossible to determine rheological parameters of liquid crystals for this type of experiment. The purpose of our work was to modify the classical equations in order to increase the information content of the experimental data and to provide an adequate description of anisotropic liquids. The system of equations describing the dynamics of the director in space can be written as [3]

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