calphy is a Python library and command line interface for free energy calculations. calphy provides fully automated routines for calculation of free energy using interatomic potentials; which in turn can be used to calculate complex thermodynamic properties such as melting temperature, specific heat and phase diagrams.


  • Calculation of Helmholtz and Gibbs free energy.
  • Calculation of temperature dependence of free energy.
  • Direct calculation of coexistence lines in a phase diagram.
  • Alchemical transformation for free energy as function of concentration.


  1. Menon, Sarath, Yury Lysogorskiy, Jutta Rogal, and Ralf Drautz. “Automated Free Energy Calculation from Atomistic Simulations.” ArXiv:2107.08980 [Cond-Mat], July 19, 2021.

  2. Freitas, Rodrigo, Mark Asta, and Maurice de Koning. “Nonequilibrium Free-Energy Calculation of Solids Using LAMMPS.” Computational Materials Science 112 (February 2016): 333–41.

  3. Paula Leite, Rodolfo, and Maurice de Koning. “Nonequilibrium Free-Energy Calculations of Fluids Using LAMMPS.” Computational Materials Science 159 (March 2019): 316–26.

Doctoral student

Doctoral student at Ruhr Universität Bochum and an aspiring scientific programmer with an interest in Python and C++.