text: An example of sorption of ligands occurs in metallic oxides and silicate surfaces. In a mineral surface, the metal ion acts as a Lewis acid, and the ligands act as the Lewis base. For ligands that have protons, the sorption is dependent on the pH.
  In cases of where ligands affect the surface coordination by performing a redox reaction, the sorption phenomenon are then referred to as adsorption. This is of particular importance because different surfaces and ligands have varying redox intensity that can catalyze various reactions.