Density functional theory of adsorption in pillared slit-like pores

Density functional approach to the description of fluids in contact with bilayers

“…In the above C is a constant, the precise value of which is irrelevant if the total number of grafted chains is fixed. 17,18,22,23,59 We have already mentioned the number of segments tethered at each plane in two bilayers is the same. Below, this number will be related to the density profile of segments of chain molecules.…”

“…For the sake of brevity we do not present the resulting density profile equations, since they are formally identical with those reported in our recent works. 17,18,22,23 The solvation force ͑per unit area͒ acting between two bilayers is calculated from…”

“…In this work we did not perform comparisons of the theory with computer simulation results. However, in our previous works 17,22,64,65 such comparisons were presented for quite similar systems. They have proved that the density functional theory is capable to predict reasonably well the structure of fluids in contact with a surface modified with pinned brushes, as well as in pores modified by pillars built of chains.…”

“…Recently, density functional approaches have been successfully applied to study several systems containing complex molecules. The investigations reported in the literature have concerned the adsorption of chain [1][2][3][4][5][6][7][8][9] and polyatomic molecules of more complex geometry, [10][11][12][13] the description of the formation of tethered brushes on solid surfaces and adsorption of simple fluids on surfaces modified by attached brushes, [14][15][16][17][18][19][20][21] studies of adsorption in pores modified by pillars, 22,23 as well as studies of nonuniform polyelectrolytes and the systems involving charged brushes. 16,[24][25][26][27][28] One should also note that a simple model of a layer ͑or layers͒ of chain molecules that are terminally joined to a surface can be also used as a crude model of a membrane.…”

Studies of Capillary Phase Transitions of Methane in Metal−Organic Frameworks by Gauge Cell Monte Carlo Simulation

“…Thus, knowledge of the phase behaviors of fluids confined in porous materials is not only of interest in the physical and surface sciences but also a prerequisite for the invention of nanoscale technologies and nanomaterials. Up to date, remarkable advances have been achieved in elucidating the specifics of vapor−liquid equilibria (VLE) and capillary phase transitions in various porous matrixes. − Molecular modeling, mainly grand canonical Monte Carlo (GCMC) and Gibbs ensemble Monte Carlo (GEMC) simulations, has proved to be one of the most efficient methods for the description of these phase behaviors. − However, previous investigation has shown that, at subcritical conditions, although GCMC simulation can obtain the hysteresis loop formed by the discontinuous adsorption and desorption branches of isotherms, it cannot be used to directly determine the equilibrium phase coexistences. Similarly, as pointed by Neimark and Vishnyakov, GEMC simulation suggested by Panagiotopoulos also bears its disadvantage that the coexistence point is sensitive to the initial configuration in the nanopores with strongly attractive walls.…”