| Metal materials have been abroad used in machines, electronics, energy sources, informations, etc. Metal surfaces are the direct touch and action regions between the metal and environment, many kinds of destroys easy happen in here. But up to date it is far clear about the surface microstructures and the microcosmic mechanism of the surface phenomena. This has effected the development of the theoretics investigation and the production practice. The complexity of the surface structure and the multiformity of the surface phenomena urge people's farther studies。By using the semi-experiential potentials and first-principles method, this text systemically studied FCC transition metal surfaces structures and properties including the surface energy, surface stress, surface relaxation, surface reconstruction, surface stepped structure, surface adsorption, etc.Surface energies and surface stresses are two basic parameters to characterize the surface thermodynamics of materials. Taken Cu as an example, the surface energy and the surface stress tensors in three low index surfaces and two families of representative (hk0) and (hk0) surfaces belong to [001]-and [110]-rotating axis, respectively, have been calculated by using MEAM. For the surfaces of (hk0) and (hhl) family, with increasing the rotating angle from (100) plane and (001) plane, respectively, the surface energy and the surface stress tensors go through some certain change curves. The change curves appear some inflexions corresponding to Cu(210) and (113) surface. The kind of rule can be used to predict the surface energy and the surface stress tensors in any (hk0) or (hk0) surface. With increasing (or decreasing) the including angle between the studied plane and {100},{111} plane (or{110} plane), the anisotropy ratioτxx/τyy of two surface stress tensors lying in the surface plane increase. The anisotropy ratio is the biggest in (110) surface. From the minimum of the surface energy, Cu(111) surface is the most stable surface. For three low index surfaces, the decreasing in the surface energy is small after relaxation, while the surface stress tensors in the surface plane show an opposite change (decreasing and increasing) for inward and outward relaxations. The resulting relaxation direction is related to the normal stressτzz before relaxation.Surface relaxations and reconstructions are the most important characters of the clean surface deviating from the three dimension periodicity structure. By using MEAM and first-principles method we studied three low index surfaces relaxation and reconstruction of FCC metals Cu, Ag, Au, Ni, Pd, Pt. It found that, except Pt(111) surface is anomalous outward relaxation, other surfaces are inward relaxation. The contraction of the (110) surface is the most, and the relaxation of the (111) surface is the smallest. The contraction of the topmost interlayer spacing can be understood by the transfer of d electrons in topmost layer from high energy regions to low energy regions. It is just contrary for the outward relaxation surface. From the energy minimum principle, the (1×2) missing row (MR) reconstructions can not be formed for all (100) and (111) surfaces, while for (110) surface, the MR reconstruction can be formed naturally for Au and Pt. In addition to the surface energy explanation, the results are also related to the surface topography. Comparing with the density of states (DOS) of bulk electron, the DOS curves of the surface topmost layer in valence band regions become narrow and shift toward the Fermi level, and higher in high energy region and lower in low energy region. So the surface atoms are more active than bulk. The second layer atoms of FCC metals (110) surface also has higher electron energy state than those of (111) and (100) surfaces, so it is more active than (111) and (100) surfaces.Step is an important form of surface structure defects. Atomic steps can serve as nucleation centers and play a significant role for the morphology, energetics, reactivity and dynamic properties of the surfaces. By using first-principles USPP method, we systematically studied the relaxation trend and electronic properties of Cu(100), (111) and (110) stepped surface. It found that the interlayer relaxation trends have relationship with the atom rows in the surface terrace. For stepped Cu surface with n atom rows in the (100) or (111) terrace, the outmost n-1 interlayer spaces contract, then the nth interlayer space expansion, and the followed n+1st interlayer space contract again. And the larger number of atoms rows n in the terrace, the more of the contracted magnitude for the spacing between the topmost layer and the corner layer. For Cu(110) stepped surfaces, which have n and n-1 atom-rows in terrace and subterrace, respectively, the topmost 2n-2 interlayer spacinges contract, while the 2n-1st interlayer spacings expands, and the next 2n-1st interlayer spacing maybe expands or contracts. All three kinds of stepped surfaces are following the nearest-neighbors coordination trend. That is, the interlayer spacing between each pair of layers with the coordination smaller than the bulk contracts in the process of multilayer relaxation, and the following first bulk coordination interlayer spacing expands. All stepped surfaces are more flat after relaxation. And the bond-lengths between the step edge (first layer) atom and its nearest-neighbors do not depend on the surface termination, but only on the local coordination. Below the Fermi energy level, the DOS of the atom at the step edge have a higher peak value in the high energy regions, so the atoms at stepped edge are more instable and can be dislodged and peeled off more easily than other surface atoms. For the stepped surfaces with the same terrace and step, the DOS curves have the similar shapes for the atoms at the step edge, as well as for the atoms at the corner, the atoms at the middle of the terrace, the underneath atoms near the corner, respectively. And the DOS curves are similar for the atom having the same nearest neighbor coordination.The knowledge of the adatoms on the surface of transition metals is the basic of many physical and chemical phenomena such as corrosion, oxidation, catalysis, crystal growth, etc. By using MAEAM, the energy and perpendicular force maps of the Pt adatom on Pt (111) surface can be classified into repulsive region, transformed region, and attractive region. In repulsive and transformed regions, the energy and force maps are similar with the surface morphology. In attractive regions, the energy and force maps are more complicated than those in other regions due to the effects of the many-body interactions and nonspherical distribution of the electrons of the atoms in crystal. By using first-principles PAW method, we studied the energy, structure, electron properties and diffusion of the H atom adsorb on Pt(111) surface and in subsurface. When the coverage is 1ML, H atom occupied the fcc hollow favorably. When H atom adsorbs in subsurface, the tetrahedron sites are more stable than the octahedron sites. And the entering of the H atom in the subsurface makes the large expansion of the first interlayer spacing. The evolution of the Pt DOS is reported for different adsorption site. It is shown that the presence of H in the subsurface decrease the surface Pt chemical reactivity. The Pt DOS at the Fermi level is largely decreased and new states are localized around-7eV.
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