| Abstract
| - The systematic investigation of the hysteresis phenomena in finite-sized slitlike nanopores via theAranovich−Donohue (AD) lattice density functional theory (LDFT) is presented. The new reliablequantitative modeling of the adsorption and desorption branch of the hysteresis loop, through the formationand movement of the curved meniscus, is formulated. As a result, we find that our proposal, which closelymimics the experimental findings, can reproduce a rounded shape of the desorption branch of the hysteresisloop. On the basis of the exhausted commutations, we proved that the hysteresis loop obtained in theconsidered finite-sized slitlike geometry is of the H1 type of the IUPAC classification. This fundamentalresult and the other most important results do not confirm the results of the recent studies of Sangwichienet al., whereas they fully agree with the recent lattice studies due to Monson et al. We recognize that thenature of the hysteresis loops (i.e. position, width, shape, and the multiple steps) mainly depends on thevalue of the energy of both the adsorbate−adsorbate and adsorbate−adsorbent interactions; however, thefirst one is critical for the appearance of hysteresis. Thus, for relatively small adsorbate−adsorbateinteractions, the adsorption−desorption process is fully reversible in the whole region of the bulk density.We show that the strong adsorbate−adsorbent interactions produce (also observed experimentally) multiplesteps within hysteresis loops. Contrary to the other studies of the hysteresis phenomena in confinedgeometry via the LDFT formalism, we constructed both ascending and descending scanning curves, whichare known from the experimental observations. Additionally, we consider the problem of the stability ofboth the obtained adsorption and desorption branches of the computed hysteresis loop in finite-sizedslitlike nanopores.
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