The structures of the discotic liquid crystalline (LC) phase of metal-free octa-substituted phthalocyanine (Pc) derivatives were investigated using molecular dynamics (MD) simulations. Special attention was paid to the LC phase structure of the non-peripheral octa-hexyl substituted Pc-derivatives that were recently found to show very high carrier mobilities for the discotic LCs. We obtained spontaneous transition to the columnar hexagonal (Col_{h}) LC phase in a melting simulation from the crystal structure obtained using an x-ray diffraction study. In this simulated Col_{h} structure, the Pc-core normal vectors were tilted 47{∘} from the column axis in parallel within each column, but the tilting directions are disordered between columns. We also found that the inter-core distance was not as large as previously suggested (0.4-0.5 nm) but similar to the common value (0.36 nm). This may resolve the contradiction between the high carrier mobility of the non-peripheral substituted Pcs, because larger inter-core separations degrade the mobilities.

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The electrical resistivity (ρ) and the thermoelectric power (S) of Fe ( Sb 1− x Te x )2 were studied to investigate the electrical properties of them. The ρ- T curves for all specimens measured show semiconductive properties. The results of the ρ-T and S-T curves suggest the existence of the narrow 3d-bands between ordinary covalent bands. From the X-ray analysis it is concluded that the crystal structures of the ternary system are distorted continuously from the orthorhombic structure to the monoclinic one.