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First-principles calculation based on the GGA methods has been applied to the prediction of the properties of bulk -uranium and seven -uranium surfaces. The number of layers in the slab has great effects on the simulated surface properties. The predicted surface properties are trustworthy when the slab number is nine or more. The surface energies of the seven low index uranium surfaces are in the range from 1.756 to 2.151 J/m 2 . The hybrid between the 5 orbital and 6 orbital also has somewhat impacts on the surface energies of uranium.

First-principle calculations have been performed to study both O2 molecule and O atom adsorption on α-U(001) surface and subsurface. The results show that the long-bridge site is the most stable adsorption site for O2-U(001) and O-U(001) surface adsorption. The tetrahedral (Tet)

Density functional theory method has been employed to investigate the adsorption of H2 molecule and H atom on α‐U(001) surface. There exist four initial sites [top (A), triangle‐center (B), long‐bridge (C), and short‐bridge (D)] for H2 and H atom adsorptions on α‐U(001) surface. The Eads (adsorption energy) values on the top sites of H2‐U(001) configurations are around −0.666 eV, and H2 molecule has been elongated but not broken into H atoms. For the other three sites, the Eads values are around −1.521 eV. The long‐bridge site is the most reactive site for H2 decomposing. For the H‐U(001) configurations, the Eads are around −2.904 eV. Top site and short‐bridge site are the most reactive sites for the H atom react on the α‐U(001) surface. Our work reveals that the different reactive sites play discrepant effects on hydrogenation process. Geometric deformations, diffusion paths, and partial density of states of H2‐U(001) and H‐U(001) configurations have also been analyzed. Copyright © 2016 John Wiley & Sons, Ltd.