geneous AFs) are important for the description of adsorp-The solvation force for an associating fluid inside a slit-like pore tion, microreactor chemistry, heterogeneous catalysis, and is studied by using a singlet theory of inhomogeneous fluids. A other chemical problems. Geometrical constraints lead to a one-component system of hard spheres with an embedded sticky specific phase behavior and structure of confined systems. attractive site located inside their hard cores is chosen as a model The bulk fluid properties are essentially influenced by the of the bulk fluid. The bulk fluid is considered in the framework association; one can thus expect a cumulative or competitive of Wertheim's theory of association. Two models permitting dieffect of association and confinement. merization and characterized by different bond lengths are investi-The most successful theory of association in bulk fluids gated. It is shown that the associative Percus-Yevick approximation in conjunction with the singlet theory of inhomogeneous fluids is that proposed by Wertheim (6-9). It is based on the provide a quilitatively correct description of the solvation force Ornstein-Zernike-(OZ) like integral equation which condependence on the pore width for low and intermediate densities. tains explicitly the densities of bonded and nonbonded parti-For a fluid of short dimers the applicability of the theory is recles. Relevant closure relations are formulated in terms of stricted to low densities. An increase of the degree of dimerization partial correlation functions of bonded and nonbonded leads to an overall decrease of the value of the solvation force. Its monomers. The ideas of Wertheim's theory have been used dependence on the pore width is qualitatively similar for low and by Kierlik and Rosinberg (14-17) to construct a density high degrees of dimerization. For high degrees of dimerization the functional (DF) approach for inhomogeneous AFs and for curves possess cusps for the pore width equal to the bonding length.
AFs in slit-like (SL) pores in particular. The models of For an increasing density the oscillations of the solvation force are nonoverlapping associated monomers have been investigated observed. Their decay with an increasing pore width depend on the degree of association. However, in a whole range of the degree in this framework in detail.
of association, the distance between the first maxima is approxi- have focused on the developmately equal to the hard-sphere diameter.