Fig. 5: Band banding in longer Fe chains.
a Stacked constant-height dI/dV spectra (normalized) recorded along a line across the 27-atom chain as illustrated in the inset topography. Set point for the spectra is 700 pA, 5 mV with a modulation of 15 μV. The (Nb) tip gap Δtip ≈ 1.55 meV is indicated by white dashed lines. White dotted lines are at the same energies as in Fig. 4 and indicate the van Hove singularities of the α- and β-derived bands. b Larger range STM topography of the 27-atom chain. The position of the former 11-atom chain (Fig. 4h) is indicated in yellow (constant-current set point is 100 pA, 10 mV). A hollow-centered (HC) region of the CDW is highlighted by a yellow circle, a Se-centered (CC) region is marked in red. c A FFT-filter has been applied to the STM topography in b to remove the atomic corrugation. Dashed lines on the left of the chain serve as guide to the eye to illustrate the CDW order in the vicinity of the chain. Different sections of the chain are labeled with A–C.
