Figure 3: DFT calculation of electronic structures for low-temperature phases.

(a,b) Relaxed structure of the slab, showing a side view along with the labelling of the layers used in the electronic structure plots (a) and a top view (b). Te atoms are the larger green spheres, while the Ir are the smaller blue spheres. The borders shown are arbitrary for convenience in drawing and in particular are not unit-cell boundaries. Connections are drawn between Te atoms separated by 3.5 Å or less. (c) Projections of the density of states onto atoms in different layers. Shown are projections onto the LAPW spheres of Te p character averaged over all atoms in a given layer and between the top and bottom of the slab. The labelling of the layers is in a, and in the case of Te the notations ‘i’ and ‘o’ denote, respectively, the Te on the inside and outside of the particular IrTe₂ layer with respect to the surface. The energy zero is set to the Fermi level. (d) Projections of the density of states onto different Te atomic rows in ‘5 × 1’ surface unit cell. The numbers of 1, 2, 3, 4 and 5 represent different atomic rows in a surface unit cell, marked in b.