Purely organic solid state materials providing nanometre sized parallel channels are suited for physical property design. In this tutorial review, key materials in this field are reviewed along with new directions forming porous covalent and polymeric networks. Among many known host materials, perhydrotriphenylene (PHTP), tris-(o-phenylenedioxy)-cyclotriphosphazene (TPP) and members of the 2,4,6-tris-(4-halo-phenoxy)-1,3,5 triazine (4-X-POT) family are prime materials for hosting guest molecules featuring diverse physical functionality.

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In the case of simple vapour mixtures adsorbed by active carbons, the activity coefficients seem to depend essentially on the composition of the adsorbed phase, rather than on the degree of micropore filling. Consequently, the liquid-solid adsorption equilibrium of benzene + 1,2-dichloroethane mixtures has been investigated at 293 K, using a typical active carbon and following earlier work for adsorption from the vapour phase. This system has the advantage that the mixture is ideal in the liquid state, which provides a convenient reference for the study of the adsorbed phase. The activity coefficients, as well as the excess enthalpy of immersion of the carbon into the liquid mixtures, provide information on the modifications in the adsorbed state with respect to the ideal mixture. It is also shown that the introduction of the activity coefficients derived from the solidliquid equilibrium increases considerably the accuracy of the MyersPrausnitz-Dubinin model for the adsorption of the vapour mixtures.

Scanning pyroelectric microscopy (SPEM) was applied to investigate grown-in polarity in trans-4-chloro-4'-nitrostilbene (CNS) single crystals. Sectors {011} and {011} were scanned for cross sections perpendicular to the a-direction. A rotational analysis for {011}, {011} faces was performed for a needle like crystal turned around the a-axis. All pyroelectric experiments confirm a bipolar grown-in state of polarity for sector involving the twofold axis b. These measurements agree with theoretical force field and stochastic calculations, predicting a bipolar state and a nearly identical extent of polarity for two different sectors.

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The alignment and relaxation dynamics of a polar dye molecule, N,N-dimethyl-4(4-nitrophenylazo)aniline (DNAA), in zeolite L and perhydrotriphenylene (PHTP) channels were investigated by means of a combination of optical, dielectric, and quantum-chemical methods. Both the zeolite L and PHTP channels enable the dye molecules to align along the channel axis. An amplified net dipole moment of DNAA in PHTP is observed and attributed to enhanced 1D close alignment of dye molecules. In zeolite L channels, a concentration gradient is found with aggregation at the channel entrances. The dynamics of the dye in zeolite L channels reveals localized conical rotational fluctuation modes following Arrhenius-type activation with energy of 0.31 eV, which we assign to small noninteracting fluctuating polar units of the dyes being loosely aligned or isolated. Unlike zeolite L, relaxations in PHTP are characterized by cooperative wobbling motions interpreted as increased intermolecular dipole interaction due to a closely packed one-dimensional array. Temperature-dependent activation energies of 0.25 eV below 0 degrees C and 0.37 eV at ambient temperature reflect the role of the soft channel walls in the activation process.

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