Get GEM-Selektor binary package or build it!

GEM-Selektor v.3 (GEMS3) is a code package for thermodynamic modelling of aquatic (geo)chemical systems.

The GEMS3 package is distributed free of charge to registered users affiliated to non-profit educational and research institutions, for educational and research purposes only, subject to the Terms and Conditions of Use.

Use of GEMS3 in any commercial activity (not education or research) requires a written agreement with the vendor (Paul Scherrer Institute).

The currently available trunk variant of GEMS3  is provided without source code, in the form of an executable program with built-in thermodynamic database and help database. The source code is publicly available here and here. Starting from version 3.6.0, the source code of GEMS3GUI part is made available under the GPL v.3 license. The source code of GEMS3K kernel is available under LGPL v.3 license, as before.

GEMS3 runs under Windows, Mac OSX and Linux desktop PCs. See the GEMS3 Technical Info page for the IT-related information and for the installation instructions.

We would appreciate a non-compulsory registration of your name, affiliation, and e-mail,  as well as OS and area of potential applications.

Click here to register and download GEM-Selektor binary package

Currently available binaries: GEM-Selektor v.3.7.0 rev. b053eed.fdcdd2b (improved GEM convergence and speed, automatic compression of sublattice Berman and CEF solid solution models, improved Process wizard for SFTR mode, various minor bugfixes).

Attention: Starting from version 3.6.0, GEM-Selektor GUI (Graphical User Interface) source code is available under GPL v.3 license. People who are not afraid of computing (especially those working on Linux systems) can download git repositories of GEMS3GUI and GEMS3K and build them as described in of GEMS3GUI. To download the latest (trunk) version of the GEMS3GUI source code under GPL v.3 license, open your web browser and navigate to Follow the instructions in there (you need to have Git installed - provided by default in Macos and Linux, for Windows 10 check The current trunk HEAD corresponds to GEM-Selektor v.3.7.0.  

Enjoy GEM-Selektor v.3!

Last updated:  25. 03. 2020

Copyright (c) 2003-2020  GEMS Development Team.