This project continues the work of the Fermi–Löwdin orbital self-interaction correction (FLOSIC) Center, advancing efficient and reliable density functional theory (DFT) calculations by eliminating long-standing self-interaction errors. Building on prior funding under DE-SC0018331, the Center has already delivered substantial progress in theory, code development, and validation, establishing FLOSIC as a rigorous alternative to error-cancellation approaches in conventional DFT. Earlier results clarified fundamental limitations of widely used correction schemes, including the discovery that the Perdew–Zunger self-interaction correction introduces errors in the uniform-density limit where standard DFT is otherwise exact. Additional theoretical advances have shown that density-corrected DFT improvements rely on error cancellation, whereas FLOSIC achieves accuracy by construction, yielding correct results for physically meaningful reasons. The project also established formal links between Fermi orbital descriptors (FODs), electron localization, and underlying many-body wavefunction properties, providing both a theoretical foundation and practical strategies for generating optimal localized orbitals. The University of Texas at El Paso (UTEP) contribution focuses on extending FLOSIC to more complex and computationally demanding regimes. Work during this period emphasizes completing advanced implementations of the method, exploring downward quantum learning strategies, and developing chiral periodic formulations suitable for extended systems. Together, these efforts strengthen the theoretical rigor, computational reach, and applicability of FLOSIC, supporting more accurate electronic structure calculations across chemistry, materials science, and condensed-matter physics.