defermi: A tool for computing and visualizing point-defect equilibria, bridging computational and experimental users

Using computational methods to study defect thermodynamics is a powerful alternative to the assumptions-based defect chemistry approach. Currently available tools for the computation and visualization of point-defect equilibria primarily focus on DFT high-throughput schemes, resulting in a significant entry barrier. To bridge the gap between computational applications and the more experimentally focused defect chemistry approach, we report defermi, a Python package with a graphical user interface. The GUI is designed to provide fast and consistent workflows for plotting formation energies and charge transition levels, and for computing Brouwer and doping diagrams. The Python API provides the same high-level interface, while offering additional customization capabilities, including full control over the routines used to compute formation energies and defect concentrations. This opens the door to extending the current computational approach to include temperature and volume dependence in defect formation energies, which are generally neglected in ab initio approaches.