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A simple and convenient method for the synthesis of twelve novel alkadiynoic acids, HOOC(CH2)mC[tbnd]C-C-C[tbnd](CH2)n-CH3, is reported.

Polymerizable diacetylenic lipids form a long, hollow tubular bilayer microstructure that has been characterized by microscopy, spectroscopy and x-ray diffraction. The lipid monomers are highly ordered at the molecular level, and at high density the microstructures themselves align giving macroscopic order.

A study of the Raman spectra of the alkoxyazoxybenzenes has revealed new bands which change markedly in all phases. Evidence is presented that indicates the existence of different alkoxy tail conformations between all observed phases. A tentative assignment of a band associated with an accordion mode is made. The possible effects of these results on mesophase stability are discussed.

Gas-liquid chromatography (glc) was used in a theimodynamic investigation of solubility in a 1.743:1.000 (weight: weight) mixture of Cholesteryl chloride and Cholesteryl myristate. This mixture exhibits a β cholesteric phase (increasing pitch with increasing temperature) at low temperatures, a “nematic point” at 42°C, and an α cholesteric phase (decreasing pitch with increasing temperature) up to 62°C, where a transition to the isotropic liquid takes place. Infinite dilution activity coefficients and partial molar enthalpies of solution were obtained for 16 diverse nonmesomorphic solutes in the β and α phases. The results are interpreted in terms of a statistical thermodynamic model2 of solution in anisotropic solvents. Comparison of solubility behavior in the α and β phases suggests a pronounced difference in the molecular packing of the two phases. Evidence is presented that the β→α transition may involve a higher order thermodynamic phase transition at the “nematic point”.