Recent advancements and challenges in orbital-free density functional theory

Orbital-free density functional theory (OFDFT) stands out as a many-body electronic structure approach with a low computational cost that scales linearly with system size, making it well suitable for large-scale simulations. The past decades have witnessed impressive progress in OFDFT, which opens a new avenue to capture the complexity of realistic systems (e.g., solids, liquids, and warm dense matters) and provide a complete description of some complicated physical phenomena under realistic conditions (e.g., dislocation mobility, ductile processes, and vacancy diffusion). In this review, we first present a concise summary of the major methodological advances in OFDFT, placing particular emphasis on kinetic energy density functional and the schemes to evaluate the electron-ion interaction energy. We then give a brief overview of the current status of OFDFT developments in finite-temperature and time-dependent regimes, as well as our developed OFDFT-based software package, named by ATLAS. Finally, we highlight perspectives for further development in this fascinating field, including the major outstanding issues to be solved and forthcoming opportunities to explore large-scale materials. This article is categorized under: Electronic Structure Theory > Density Functional Theory Software > Simulation Methods Quantum Computing > Theory Development