Orbital-free density functional theory (OFDFT) has reemerged as a viable alternative to Kohn-Sham DFT, driven by recent advances in kinetic energy density functionals (KEDFs). Nonlocal KEDFs have significantly extended OFDFT's applicability, particularly for bulk solids, but their high computational cost and dependence on system-specific parameters limit their universality. In this work, we propose a semilocal KEDF at the generalized gradient approximation level that achieves accuracy comparable to the state-of-the-art semilocal functionals while remaining parameter-free. Our construction revives the Thomas-Fermi–von Weizsäcker (TFvW) framework by modulating the relative contributions of TF and vW terms through physically motivated constraints and preserving the exact second-order gradient expansion. Despite its simple form, the proposed functional (KGE2) performs well across both extended systems (metals and semiconductors) and finite systems (clusters), without any need for empirical tuning. These results mark a step toward the development of transferable and computationally efficient semilocal KEDFs for large-scale OFDFT simulations.

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• Electronic structure
• Electronic structure of atoms & molecules
• First-principles calculations
• Crystal structures
• Density functional theory