PyES, an open-source software for the simulation of thermodynamic equilibria

The study of chemical equilibrium is an often overlooked topic in modern chemistry. While not being particularly spectacular, fancy or usually talked about, the topic is of uttermost importance spanning multiple fields of applications: from bio medics to environmental chemistry the understanding of the fundamental equilibrium of chemical species can shed a light on many phenomena. In pur current era is difficult to think of a field of study who does not benefit from the assistance of dedicated IT tools to aid researchers in their work. From a survey conducted among the participants of the Network for Equilibrium and Chemical Thermodynamics Advanced Research (COST ACTION – NECTAR CA18202) it surfaced the need for new and improved computer tools for the study of thermodynamic equilibrium. For this reason, we decided to write PyES: a free, open-source, modern and multi-platform Python application for the simulation of chemical titrations and species distributions. Originally envisioned as the spiritual successor of ES4, a terminal based software with the same scope of application, written in the BASIC between the ‘70s and ‘90s by a research group of the University of Messina, PyES evolved past it increasing the stability of the original algorithm, estimating uncertainty of obtained results, considering the precipitation of solids as well, all wrapped in a GUI front end with graphing capabilities and the possibility of exporting results to allow interoperability with other tools.