Figure 1

The band structures from $\Gamma$ to $J$ of the Ge(001)-$c(4\times 2)$ surface calculated using (a) a six-layered slab and (b) a ten-layered slab. The Fermi energy $E_F$ is set to zero and indicated by gray dashed lines. The filled black balls indicate the states with bulk derived features. The empty balls stand for the back bond state and the half-filled ones for the surface resonance between the back bond state and the bulk state. The big circle indicates the resonance region. The empty squares indicate the $\pi$ dangling bond state and the half-filled squares for the $\pi$ mixed with the bulk state. The charge densities of (c) the bulk state and (d) the back bond state at $\Gamma$ in band structure (b) are plotted on the right. The isosurface value is $6.0\times {10}^{-4}\mathrm{e}/{\AA }^3$. The green balls stand for Ge atoms and white balls for H atoms.Reuse & Permissions