Structure analysis of the Ta(0 0 1)1 × 1–H surface

Surface structure of H-adsorbed Ta(0 0 1) surface for saturation coverage at room temperature has been studied by low energy electron diffraction (LEED), a symmetrized automated tensor LEED program and high-resolution electron energy loss spectroscopy (HREELS). The optimized structure is that H atoms are adsorbed at a threefold hollow site taking four symmetrically equivalent sites in the unit cell of the unreconstructed Ta(0 0 1) surface. The layer separation between the H atom and the topmost Ta atom layer is 0.16 Å and atomic distance between the H atom and the first layer Ta atom is 1.94 Å and that between the H atom and the second layer Ta atom is 1.92 Å, which agree well with the sum of hard sphere radii of H (0.5–0.6 Å) and Ta atom (1.43 Å).