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Magneto-orientation effects were observed for platelets of thin layered single crystals of L- and DL-dipalmitoylphosphatidylcholine (DPPC), and for single crystals of polyethylene (PE) suspended in xylene. For both L- and DL-DPPC crystals, a biaxial magneto-orientation was observed, in which both directions of hydrocarbon chain and phosphorylcholine group were directed perpendicular to the applied field direction. For PE, the hydrocarbon chain direction was oriented perpendicular to the field.From the orientational behaviour under the magnetic field, the anisotropy of diamagnetic susceptibility, the difference between susceptibilities parallel and perpendicular to the hydrocarbon chain direction, is evaluated as - 9 × 10-8 and - 1 × 10-8 emu/cm3 for L-DPPC and PE, respectively.The origin of the diamagnetic anisotropy of DPPC is briefly discussed in terms of the molecular and crystal structures.

By use of the torsional quartz crystal method, the real and imaginary parts of the complex shear mechanical impedance of several nematogenic materials were measured as functions of the temperature at frequencies ranging from 50 to 150 kHz. From the impedance, we have determined the real and imaginary parts of the complex shear viscosity, in which a remarkable pretransitional anomaly is observed in the isotropic phase near the isotropic-nematic phase transition temperature, Tc. In the nematic phase and the isotropic phase except for the vicinity of Tc, the Newtonian behaviour is observed.The behaviour of the complex shear viscosity in the isotropic phase has been analyzed by the theory of de Gennes, and it is shown that the observed behaviour can be well described by the theory.