This user guide is designed to accomplish three goals: 1) to familiarize users with the appropriate background knowledge of the thermodynamics and datasets upon which MELTS is based; 2) to facilitate use of the software and offer real-world, tested tips to move users past moments of extreme frustration; and 3) hopefully, to inspire new avenues of MELTS-based investigations.  If you are new to MELTS or have tried to incorporate it into your work in the past and been frustrated by "Quadratic Minimization Failure!" or similar error messages, then look no further.  The Running MELTS section of this guide contains step-by-step instructions for installing and running the software as well as troubleshooting tips to move you past problems that invariably arise as you learn it.  If you have avoided MELTS in the past due to scarce documentation and lack of a MELTS expert in your department, let A Practical Guide to MELTS jump in to fill both roles.

The format of this user guide emphasizes the importance of understanding the theory behind MELTS before charging off to use it.  MELTS is a powerful modeling tool that can produce misleading results for those who do not take the time to understand it.  After reading this guide, you should be able to identify appropriate questions to investigate using MELTS, anticipate and avoid problems with proposed MELTS projects, and apply advanced MELTS techniques to add depth to these projects.  However, as with most software, the only way to become a proficient MELTS user is to work with it.  One excellent technique would be to work through the Running MELTS section and one or two examples in the Sample Problems section, and then read the preceding History and Nuts and Bolts sections before commencing your own work.

This user guide is not intended as an exhaustive review of the thermodynamic concepts underlying MELTS.

Because MELTS and its higher pressure cousin, pMELTS, share the same fundamental algorithm, methods, and graphical interface, explanations given in this guide cover both programs.  In general, the term “MELTS” refers to both MELTS and pMELTS, except where differences between the two programs are specifically noted.

A primary goal of this guide is to provide an intuitive way to think about MELTS without getting bogged down in the equations found in the papers, but to include some equations that will be familiar to students.