Adsorbed potential

The associative part of the adsorbing potential, Eq. (116), generates a highly localized adsorption which corresponds to the onefold, to the twofold bridging site, and to the fourfold hollow site adsorption dependence of the length L. Note that in the absence of the associative part, Eq. (119), and in the limit 0 the pore walls reduce to an array of hard spheres. 

The fluid is confined to a slit-like pore of width H. Each of the pore walls is the source of the Lennard-Jones (9-3) potential and the total adsorbing potential, thus... 

As mentioned before, Stern had a metal electrode in mind when he described the surface-solution interface then (7q referred to the electronic charge on the surface of the metal itself, ato the charge formed by electrostatically (or chemically) bound electrolyte ions at the IHP, and a to the charge in the diffuse layer. In the case of silver iodide, the surface charge ctq is assumed to be made up of the adsorbed "potential determining ions"... 

Oxide surfaces have usually been regarded as being similar to the Agl surface the adsorbed "potential determining ions," H+ and OH, form the charge CTq, and a and o2 are as... 

CO adsorbing potential [mV] 0CO Qco (COad oxidation electric charge) [mC] Nco... 

TiCl4 [88], Fe(CO)s [89], Au precursor [90] Metal CVD precursors react with dangling bonds at elevated sample temperature to form regions of metal adsorbates. Potential application in the fabrication of metallic nanoscale devices. 

The total potential between the adsorbate molecules and the adsorbent is the sum of the total adsorbate-adsorbate and the adsorbate-adsorbent potentials ... 

The adsorbent has only a secondary effect on the adsorbate-adsorbate interaction. For this reason, we will focus our attention on the second term, adsorbate-adsorbent potential, and refer to this term as [Pg.82]

There are three basic types of contributions to the adsorbate-adsorbent interactions dispersion, electrostatic, and chemical bond. The latter, chemical bond, has been explored for adsorption only recently. Weak chemical bonds, particularly the broad type of bonds involving n electrons, or 7r-complexation, offer promising possibilities for designing new and highly selective sorbents. The subject of Tr-complexation sorbents will be discussed in a separate section. For physical adsorption, the adsorbate-adsorbent potential is... 

In addition to the form of in first-layer absorption, its magnitude is also of significance as regards validity or relative importance of Model 2. Here it is assumed that Model 2 may be based on dispersion forces with polarizations to produce larger than normal first-layer adsorbate-adsorbent potentials (the a term in Equation 6b) and longer than normal range adsorbate-adsorbate repulsions. One may evaluate a and b by curve fitting as follows ... 

Adsorbent-adsorbate potential energy calculations have been made for the adsorption of argon in the channels and intersections of Silicalite-I (Muller et al., 1989). The most favourable sites for localized adsorption are within the straight and sinusoidal channels, which together should be able to accommodate 20 molec uc-1. At a loading of 24 molec uc 1 all the available sites in the channels and intersections are probably occupied by localized molecules. 

If the dissociation of the ionizable groups on the particle surface is not complete, or the configurational entropy Sc of adsorbed potential-determining ions depends on N, then neither of ij/o nor of cr remain constant during interaction. This type of double--layer interaction is called charge regulation model. In this model, we should use Eqs. (8.35) and (5.44) for the double-layer free energy [ 11-13]. 

The simple model described by eq. 11.5 should serve as a useful starting point to test non-adiabatic interfacial ET theory. The predicted dependence on electronic coupling, density of semiconductor states, adsorbate potential and reorganisation energy can be tested experimentally. As shown in Fig. 11.6, the calculated injection rate increases the further the adsorbate excited-state oxidation potential lies above the conduction band edge. The variation is slow high above the band edge, but... 

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