Filled SAphases in binary liquid crystalline systems of terminal‐nonpolar compounds (III). The role of the molecule length of the rod‐like component

The phase diagrams of 8 binary systems of liquid crystals are presented whereby one component is a “biswallow tailed” compound and the second component is a member of the homologous series of 4,4′‐bis‐n‐alkyloxy‐azoxybenzenes. In all phase diagrams studied induced smectic A phases occur. X‐ray investigations give evidence that in the binary systems of short‐chain homologues the layer spacing d of the smectic A phase is clearly greater than the average molecular length L̄, whereas in the systems of long‐chain homologoues d is found to be somewhat smaller than L̄. The results are interpreted on the basis of a simple packing model.