History of FactSage, the CRCT, etc.


F*A*C*T - Facility for the Analysis of Chemical Thermodynamics - started in 1976 as a joint research project between two universities, the École Polytechnique (Professors Christopher W. Bale & Arthur D. Pelton) and McGill University (Professor William T. Thompson), for treating thermodynamic properties and calculations in chemical metallurgy. Partial funding for the project was provided by a Cooperative Grant from NSERC - Natural Sciences and Engineering Research Council of Canada. Rights and control were assigned to the company Thermfact Ltd./Lteé.

The initial programs were written in FORTRAN on punched cards and performed chemical thermodynamic calculations involving pure substances and ideal gases. In 1979 F*A*C*T On-Line was offered as an interactive program through the McGill University MUSIC system accessed via Datapac and Telenet telephone links. Solution programs and databases were added together with the POTCOMP and TERNFIG algorithms for optimizing, calculating and plotting binary and ternary phase diagrams. At this time F*A*C*T started to incorporate the Gibbs Energy minimizer, SOLGASMIX, developed by Dr. Gunnar Eriksson, GTT-Technologies.


In 1984, the research centre CRCT - Centre de Recherche en Calcul Thermochimique / Centre for Research in Computational Thermochemistry, was founded at the École Polytechnique (the engineering faculty of the Université de Montréal) by Professors Arthur D. Pelton & Christopher W. Bale.

In addition to training engineers and scientists, the mandate of the CRCT is undertake research and development of thermodynamic models and data for different types of phases and solutions, techniques for estimating phase diagrams of multicomponent sytems, and methods for representing and calculating complex chemical equilibria. The Centre actively participates in contractual, grant and applied research projects often in collaboration with industry, government and university groups from other countries. Typically there are about 20-30 people (students, professors, support staff) working in the Centre. A principal activity of the CRCT is the the promotion and development of F*A*C*T.

Fact-DOS, -Web, -Win

In the 1990's F*A*C*T evolved into PC-based programs. FACT-DOS (1994) offered unlimited access to the software and databases. FACT-Web (1996) provided interactive demonstration modules through the Internet at the CRCT. The Windows® version FACT-Win (1999) offered a fully integrated thermochemical database system that coupled proven software with self-consistent critically assessed thermodynamic data. By this time F*A*C*T had expanded well beyond chemical metallurgy and was being employed in other fields of chemical thermodynamics by pyrometallurgists, hydrometallurgists, chemical engineers, corrosion engineers, inorganic chemists, geochemists, ceramists, electrochemists, environmentalists, etc.


After more than 20 years of collaboration on software development FactSage® 5.0 was released in 2001. It is a common product of the F*A*C*T Group (Thermfact Ltd./CRCT, Montreal) and the ChemSage/ChemApp Group (GTT-Technologies, Germany). It offers in a Windows® environment of most of the features available in the FACT-Win 3.05 and ChemSage 4.0 packages. The modules in FactSage include View Data, View Figure, Compound, Solution, Reaction, Predom, EpH, Equilib, Phase Diagram, Mixture and Results.

WWW.FactSage.com is the FactSage home page and provides general information. FactSage Information lists the FactSage addresses, developers, collaborators, etc. and FactSage FAQ answers most of the common questions.

The most recent version, FactSage 8.0, was released in 2020.

FactSage is installed in hundreds of universities, government laboratories and industrial research centres around the world where it is used as a research tool and educational aid. While an understanding of chemical thermodynamics is necessary in order to run the programs, it is not essential to be an expert in the field. FactSage is a powerful self-teaching aid. With regular program usage one can rapidly acquire a practical understanding of the principles of thermochemistry especially as these relate to complex phase equilibria. For pricing and leasing costs please click on FactSage Purchase.


The FactSage databases are the largest set of evaluated and optimized thermodynamic databases for inorganic systems in the world. These databases have been under constant development since 1990. During the period 2001-2003, major additions and modifications were made as part of the FACT Database Consortium Project with funding from the Natural Sciences and Engineering Research Council of Canada and 15 industries (Noranda, INCO, Teck Cominco, Rio Tinto, Alcoa, Shell, Corning, Dupont, Pechiney (now Alcan), St. Gobain Recherche, Schott Glass, Sintef, Norsk Hydro, Mintek, IIS Materials). The updated databases were publicly released in 2004 for the first time, so the present databases are much expanded beyond what was available in the former FS50 FACT databases.

The solution databases (for solutions of oxides, salts, metals, etc.) have all been developed by evaluation and "optimization" of data from the primary literature. Based on proper thermodynamic models for every phase, all available thermodynamic and phase equilibrium data for a system are evaluated simultaneously in order to obtain one set of model equations for the Gibbs energies of all phases as functions of temperature and composition. In such an "optimization", all data are rendered self-consistent, discrepancies in the data can often be resolved, and the data can be properly interpolated and extrapolated. In particular, properties of multicomponent solutions can usually be estimated with good accuracy from the optimized model parameters of their binary and ternary sub-systems. The resulting database of model parameters can be used for calculating phase equilibria and thermodynamic properties using the FactSage Gibbs energy minimization software.

FactSage accesses both "solution" databases (.sda or .sdb files) and "pure compound" databases (.cdb files). The former contain the optimized parameters for solution phases. The latter contain the properties of stoichiometric compounds, either obtained from optimizations or taken from standard compilations.

Extensive documentation and phase diagrams on each individual database is available at FactSage Database Documentation


For pricing, leasing and other information about FactSage Software and databases please contact one of our Representatives.


A CRCT/FactSage Newsletter is published several times per year. To subscribe or view past newsletters go to Newsletter.