Fig. 4

Electronic properties. a Electronic dispersion curves of YNiO₃ along different high-symmetry line of the Brillouin zone of the \(Pm\bar 3m\) phase (FM case, majority spins): Γ = (0, 0, 0), X = (1/2, 0, 0), M = (1/2, 1/2, 0), and R = (1/2, 1/2, 1/2). The Ni 3d e _g bands are highlighted in green. The Fermi energy corresponds to the horizontal blue line. The point q _c = (1/4, 1/4, 1/4) is located by vertical dashed blue lines. b–g Electronic dispersion curves around the Fermi energy E _f (FM order, majority spins) along high-symmetry points (coordinates in pseudocubic notations) in the Brillouin zone of the Pbnm or P2₁/n 20-atom cell, in which bands have been folded respect to a. Consecutive panels show the evolution of the dispersion curves when freezing into the \(Pm\bar 3m\) phase increasing amplitudes of oxygen rotations (Q _R = Q _M = b 0%, d 50%, e 75%, or f 90%, lines) and eventually adding the breathing distortion (Q _B = 100% and Q _R = Q _M = c 0% or g 90%, dashed lines)