A MACROSCOPIC APPROACH TO THE ADSORPTION POTENTIAL SHIFT AT THE AIR SOLUTION INTERFACE

Changes in surface potential of water DELTA(chi)w upon adsorption of organic solvents were calculated by means of the Helmholtz equation with "macroscopic" parameters. Reasons for this choice are illustrated. The results indicate good qualitative and satisfactory quantitative agreement with the experimental data. The choice of the various parameters is discussed. The form of the dependence of DELTA(chi)w on the adsorbate concentration indicates the presence of lateral interactions between adsorbate and water whose description in terms of macroscopic parameters is under investigation.