Structure and energetics of Cu(100) vicinal surfaces

The multilayer surface relaxations of the Cu(100) vicinals are investigated using a first-principles local density technique. In agreement with the low-energy electron diffraction data for (115) and (117) 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 (10n) surfaces we conclude formation of distorted octahedral Cu islands on Cu(100) with the longer edges along the (110) direction. (C) 2001 Elsevier Science B.V. All rights reserved.