Calc.  SED & PREDOM

PREDOM: Predominance Area Diagrams

Introduction

PREDOM is a program to calculate and draw predominance area diagrams. Such a diagram shows which of the aqueous species, that are formed by a given “main” component (usually a metal cation), dominate at a given point (i.e., at given concentrations of the “ligand” components). For solid phases, a predominance area diagram shows the range of existence for solids formed by the “main” component. Therefore, it shows where a solid phase is thermodynamically stable (even if the amount of solid formed at equilibrium is perhaps very small).

This program can draw diagrams with either log(Tot.Conc.) or log(activity) as variables in the axes.