Charge transfer coefficient partial

Figure 6.23. Effect of partial charge transfer coefficient XD on catalyst performance for fixed X.A depending on dimensionless potential n, (a) electrophobic, (b) electrophilic, (c) volcano-type, (d) inverted volcano-type.

Xa partial charge transfer coefficient of electron acceptor A... 

Schultze and Koppitz [3] assume that g is typically of the order of 0.1 [see Eq. (18.12)]. Using this value, estimate the partial charge-transfer coefficient of the ions in Table 18.1. 

The Partial Charge Transfer Coefficient of Lorenz and Salie... 

Extrathermodynamic Estimate of the Partial Charge Transfer Coefficient from the Electrosorpion Valency... 

IV. ELECTROSORPTION VALENCY AND PARTIAL CHARGE TRANSFER COEFFICIENT IN SELF-ASSEMBLED THIOL MONOLAYERS... 

The first equation describes the reproduction of the kink site position in the process of separation of an atom from the kink site position and formation of an ad-atom. The second step represents desorption of the ad-atom. The charge transfer is split. Following the description of partial charge transfer in Section 4.3 with the introduction of a partial charge transfer coefficient A the charge transfer in the first step is = Xz, and the charge transfer in the second step Az j = (1 — A )z. The intermediate ad-atom can be a lower valent oxidation state stabilized as an anion complex. 

A formal analogy apparently also exists between the partial charge transfer coefficients d and the exchange current densities of charged species participating in the formation of the equilibrium potential of the ion-selective electrode. However, the origin of the selectivity coefficient Ki/i... 

Here X is the partial charge-transfer coefficient, namely, the fraction of electron charge transferred from a sulfur atom to the mercury upon adsorption, and a is the degree of dissociation of the sulfhydryl group. Since partial electron transfer from the sulfhydryl groups and their deprotonation are strictly correlated events, a and X are expected to assume close values. The Hg notation is merely used to denote chemisorption of the RSH thiol on Hg, and has no stoichiometric implications. As a matter of fact, under conditions of total charge transfer (a = 2. = 1), formation of mercurous [3, 69] or both mercurous and mercuric [77, 79] thiolate monolayers has been postulated. However, no definite... 

Differentiating Eq. (19) with respect to CTM under the assumption that the dipole potential xt and the partial charge-transfer coefficient A, = a are not appreciably affected by a change in au, yields the following expression for the reciprocal of the differential capacity of the thiol monolayer ... 

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