chemcat: Chemistry Calculator for Atmospheres

---

Author:

Jasmina Blecic and Patricio Cubillos (see Collaborators)

Contact:

jasmina[at]nyu.edu

Contact:

patricio.cubillos[at]oeaw.ac.at

Organizations:

Space Research Institute (IWF)

Web Site:

https://github.com/AtmoLib/chemcat

Date:

Jul 29, 2025

---

Features

chemcat is a tool to compute atmospheric chemistry compositions and other thermochemical properties. The following features are available when running chemcat:

• Compute Thermochemical-equilibrium Chemistry via Gibbs Free-energy Optimization including charge conservation

• Set custom network of species in the system

• Incorporate NIST-JANAF and NASA-ThermoBuild databases

• Compute heat capacities for a mixture of gasses

Collaborators

All of these people have made a direct or indirect contribution to chemcat, and in many instances have been fundamental in the development of this package.

• Jasmina Blecic (NYU-Abu Dhabi)

• Patricio Cubillos (IWF) patricio.cubillos[at]oeaw.ac.at

Documentation

• Getting Started
  • System Requirements
  • Install
  • Quick Example
• Chemistry Tutorial
  • Basic run
  • Custom compositions
  • Charge conservation
• Databases Tutorial
  • Look up by atom
  • Look up by atomic number
  • Look up by number of atoms
  • Look up ionic species
• API
  • chemcat
  • chemcat.cea
  • chemcat.janaf
  • chemcat.utils
• Contributing
  • Raising Issues
  • Programming Style
  • Pull Requests
• License

Be Kind

Please cite this paper if you found chemcat useful for your research:

Cubillos, Blecic, et al. (2024): Radiative and Thermochemical Equilibrium Calculations and Application for Warm-Jupiter Exoplanets.

We welcome your feedback or inquiries, please refer them to:

Patricio Cubillos (patricio.cubillos[at]oeaw.ac.at)
Jasmina Blecic (jasmina[at]nyu.edu)

chemcat is open-source open-development software under the GPL-2.0 License.
Thank you for using chemcat!