Fig. 4: Model of PNR structure from DFT calculations.

a Top view showing the armchair PNR structure. P atoms are in purple, Ag atoms in gray. The 2 × 3 unit cell is indicated by the red parallelepiped. b Side view showing the atoms of the P chains lying flat on the Ag substrate. c Simulated (left) and experimental (right) STM images. d (upper panel) The calculated DFT band structure of the whole 4P/(2 × 3)-Ag(111) surface along the K–Γ–M path of the (1 × 1)-Ag(111) surface using 160 k-points. d (lower panel) The superposition of the experimental and the calculated ARPES shows an excellent agreement.