UnReal-B : Real-Space DFT Solver for Matter in Extreme Magnetic Fields

Abstract

As new observational technologies reveal increasingly detailed properties of neutron star surfaces, the demand for accessible and extensible theoretical modeling tools continues to grow. We present UnReal-B, a real-space Density Functional Theory solver for one-dimensional chains of matter in extreme magnetic fields $B \approx 10^{12} - 10^{15},\mathrm{G}$. By employing the adiabatic approximation, UnReal-B, provides a streamlined numerical framework for calculating the electronic structure of strongly magnetized condensed matter. The solver is benchmarked against published results for several astrophysically relevant elements, demonstrating excellent agreement while maintaining a comparatively simple and transparent implementation. Released as open-source software, UnReal-B facilitates reproducible and community-driven investigations of neutron-star surface matter and provides a foundation for future developments motivated by emerging observational constraints.