5.1 I already know about ChemSage and/or FactSage, how does ChemApp differ from it?

The following are the main differences between ChemApp and ChemSage, as well as its successor FactSage

  • ChemSage/FactSage are interactive, standalone programs. They do not need any other tools apart from thermochemical data-files or databases. They are the tools of choice for users who do not wish to do any programming work. Compared to ChemApp, ChemSage/FactSage have only limited support to handle complex sets of repetitive calculations.
  • ChemSage/FactSage have a menu interface and graphical output, and are thus better suited to quickly analyze problems and what-if scenarios in which a graph on screen or paper are regularly desired. For that purpose, ChemSage/FactSage are often used alongside ChemApp.
  • ChemSage/FactSage can automatically calculate phase diagrams. If a user needs to calculate phase diagrams frequently, ChemSage/FactSage are the right programs to use. To add this feature to ChemApp would require the user to do extensive programming work.


The following are the main common features between ChemApp and ChemSage


  • ChemApp and ChemSage/FactSage internally use the same code to calculate the chemical equilibrium (see section 6.1). Results of equilibrium calculations are thus identical between both programs.
  • Related to the above, both programs also support the same wide range of non-ideal mixture phase models (-> ChemApp documentation light / regular).
  • ChemApp and ChemSage use the same thermochemical data-file format. If you have already data-files for ChemSage, they can be used for calculations with ChemApp just as well. FactSage uses its own thermochemical database format, but data-files for ChemApp/ChemSage can be easily created.