Structure and energetics of Cu(1 0 0) vicinal surfaces

The multilayer surface relaxations of the Cu(1 0 0) vicinals are investigated using a first-principles local density technique. In agreement with the low-energy electron diffraction data for (1 1 5) and (1 1 7) surfaces we find a large inward relaxation of the step atoms and an about −9% reduction of step heights rather independently of the terrace width. For the further layers we predict the interlayer contraction/expansion trends correctly but the calculated values are too high compared with experiments. From the extracted surface energies and step formation energies of (1 1 n) and (1 0 n) surfaces we conclude formation of distorted octahedral Cu islands on Cu(1 0 0) with the longer edges along the 〈1 1 0〉 direction.