GEMINI : Gibbs Energy MINImizer

GEMINI softwares are thermochemical equilibria calculation codes specially developed to take into account :

The method used is a minimization of the total Gibbs energy of the system under either constant pressure or volume conditions. The minimization method is based on a general optimization technique which has been applied to the chemical equilibrium problems.

The minimum of the Gibbs energy is found subject to :

·         the mass balance conditions

·         the non-negative condition (the mole values cannot be negative).

·         The initial composition

·         The chosen process (isotherm, adiabatic, constant volume or pressure).

The calculation outputs supply all the basic informations concerning a calculated equilibrium state :

Automatic iteration capabilities are offered, either in temperature or composition.

The datafiles can be directly created with the software COACH, or the user can create his own ones with a text editor.


This code is used if condensed species have fixed activities.

To see a numerical result, click here.

This software, really easy to use, will be extremely useful for all those working in chemical engineering : chemists, material scientists, ceramics, involved in the treatment of thermochemical equilibria.

Demo version for Windows : please contact us


The thermodynamic modeling of substances and solutions is programmed in the code. Substances are described by using a general formula of the Gibbs Energy as a function of temperature with several ranges.
The generalized multisublattice model, including the substitution model and the non ideal associate model, is used to describe Gibbs Energy of solutions.

GEMINI2 allows the user to solve very complex multicomponent multiphase equilibria problems (equilibrium composition, constituents properties, phase diagrams).
The software allows the user to tabulate, numerically or graphically, thermodynamic functions of substances and solutions.

To see a numerical complex calcul, click here.

Demo version for Windows :






updating : 01/02/04