Inverse gas-solid chromatography is used to study the adsorption of vapors of organic compounds with different structures and polarities on a carbon adsorbent modified with a monolayer of 4-(3-hydroxypropyloxy)-4'-formylazobenzene (HPOFAB) polar LIQUID crystal. The resulting thermodynamic characteristics of adsorption on the original and modified adsorbents are compared. The effect the nature and structure of adsorbate molecules and the liquid crystal modifier have on the thermodynamic characteristics of adsorption is considered.

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A quantum-chemical semi-empirical PM3 and Gaussian 09 method has been used to evaluate the structure of a monolayer of αand β-cyclodextrins on a carbon surface. The adsorption energies for various types of packing of cyclodextrin molecules in a dense monolayer have been calculated. It has been established that the monolayers with the "sideway" orientation of the cyclodextrin molecules to the carbon surface are most energetically favorable.

The isomer-selective properties of the carbon adsorbent Carbopack Y modified by successively applied immiscible monolayers of 4-n-octyloxy-4'-cyanobiphenyl mesogen and β-cyclodextrin have been studied. It has been shown that the bilayer modified adsorbent has a high selectivity to structural and optical isomers under the conditions of the gas-adsorption chromatography. Thermodynamic justification of the selectivity and its temperature dependence has been given. Compensation temperatures for the reversal of the isomer conversion from the chromatographic column have been calculated.

The features of the monolayer structure of supramolecular liquid crystals (LC) and «supramolecular LC − β-cyclodextrin» bilayers placed on a flat carbon surface are presented. The application possibility of these materials in gas-adsorption chromatography is discussed. It is shown that self-organizing ordered planar structures of these modifiers on the adsorbent-carrier carbon surface provide high meta-/paraand ortho-/para-selectivity as well as enantioselectivity to non-polar and polar optical isomers.