The Original HK Slit-Shaped Pore Model

The basis for obtaining the energy profile in a pore is the Lennard-Jones 6-12 potential  

Halsey and co-workers gave the interaction energy of one adsorbate molecule with a single infinite-layer plane of adsorbent molecules to be (Sams et al., 1960) 

Everett and Fowl (1976) extended the above result to two parallel infinite lattice planes whose nuclei are spaced at distance L apart  

Further, Horvath and Kawazoe (1983) proposed that the potential is increased by the interaction of adsorbate molecules within the pore. They included this additional interaction by adding an adsorbate dispersion term (NaAa) in the numerator of the depth of potential energy minimum Ns/la ) in Eq. 4.6 as follows  

However, no clear justification could be found in the literature for incorporating the adsorbate-adsorbate-adsorbent interaction in this manner. Further, e(z) in Eq. 4.9 may be split as follows  

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