Computer calculation of equilibrium concentrations in mixtures of metal ions and complexing species.

A method is described for calculating equilibrium concentrations of all species in multi-metal-multi-ligand mixtures from the pH of the solution, the total concentration of each metal and each complexing agent, and the relevant equilibrium constants (pK(a) values and stability constants). No restriction is imposed on types of possible complexes, which can include mixed, hydrolysed, protonated and polynuclear species. Two examples are given. One of these comprises a 10-metal-10-ligand system (195 equilibrium constants). In the second system, mixed complex formation is important. The computer program is given.