relative adsorption

https://doi.org/10.1351/goldbook.R05257
If \(\mathit{\Gamma}_{i}^{\sigma}\) and \(\mathit{\Gamma}_{1}^{\sigma}\) are the @[email protected] concentrations of components i and 1, respectively, with reference to the same, but arbitrarily chosen, @[email protected], then the relative adsorption of component i with respect to component 1, is defined as \[\mathit{\Gamma}_{i}^{\left(1\right)} = \mathit{\Gamma}_{i}^{\sigma}- \mathit{\Gamma}_{1}^{\sigma}\ \frac{c_{i}^{\alpha}- c_{i}^{\beta}}{c_{1}^{\alpha}- c_{1}^{\beta}}\] and is invariant to the location of the @[email protected] Alternatively, \(\mathit{\Gamma}_{i}^{\left(1\right)}\) may be regarded as the @[email protected] concentration of \(i\) when the @[email protected] is chosen so that \(\mathit{\Gamma}_{i}^{\sigma}\) is zero, i.e. the @[email protected] is chosen so that the reference system contains the same amount of component 1 as the real system. Hence \(\mathit{\Gamma}_{1}^{\left(1\right)}\equiv 0\).
Source:
PAC, 1972, 31, 577. (Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry) on page 591 [Terms] [Paper]