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As the fate, transport and bioavailability of U(VI) in subsurface environments are strongly influenced by its adsorption structures on iron minerals such as hematite, we systematically studied the molecular-scale structures of U(VI) complexes formed at the interfaces of hematite and water with periodic density-functional theory (DFT) calculation, extended X-ray absorption fine structure (EXAFS) measurements, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM) integrated with X-ray energy dispersive spectroscopy (XEDS). The combined theoretical and experimental results revealed that U(VI) was complexed on three hematite facets in an inner-sphere coordination, but edge-sharing bidentate mononuclear (2E) complexes were formed on {001} facets, and corner-sharing bidentate binuclear (2C …