Low-energy electron diffraction analyses of stabilized {001}-(1 x 1) surfaces revealed the atomic structure to be a relaxed bulk termination. The first and second inter-layer spacings were contracted by about 2 and 2.8%, respectively, of the bulk spacing along <001>. Photo-emission experiments with synchrotron radiation of reconstructed {001}-(5 x 20) revealed a surface resonance band above the bulk d-bands which exhibited dispersion, with photon energies of between 14 and 24eV. This was consistent with the buckled nature of the hexagonal over-layer which was responsible for the surface reconstruction. All of the remaining features of the photo-emission spectra from {001}-(5 x 20) could be predicted, on the basis of Eckardt-Fritsche-Noffke self-consistent relativistic calculations, to within 0.4eV.

S.C.Wu, H.Li, J.Quinn, D.Tian, Y.S.Li, A.M.Begley, S.K.Kim, F.Jona, P.M.Marcus: Physical Review B, 1994, 49[12], 8353-9