Pressure/temperature/substitution-induced melting of A-site charge disproportionation in Bi_(1-x)La_(x)NiO_3 (0 =< x =< 0.5)

Abstract

Metal-insulator transitions strongly coupled with lattice were found in Bi1-xLaxNiO3. Synchrotron X-ray powder diffraction revealed that pressure (P ~ 3 GPa, T = 300 K), temperature (T ~ 340 K, x = 0.05), and La-substitution (x ~ 0.075, T = 300 K) caused the similar structural change from a triclinic (insulating) to an orthorhombic (metallic) symmetry, suggesting melting of the A-site charge disproportionation. Comparing crystal structure and physical properties with the other ANiO3 series, an electronic state of the metallic phase can be described as [A3+Ld, Ni2+L1-d], where a ligand-hole L contributes to a conductivity. We depicted a schematic P-T phase diagram of BiNiO3 including a critical point (3 GPa, 300 K) and an inhomogeneous region, which implies universality of ligand-hole dynamics in ANiO3 (A = Bi, Pr, Nd,...).

24 pages, 8 figures, Phys. Rev. B in press

References in corpus (1)

• Local Magnetic Order vs. Superconductivity in a Layered Cuprate

Cited by in corpus (9)

• Theory of Valence Transition in BiNiO${}_3$
• Hybridization-switching induced Mott transition in ABO${}_3$ perovskites
• Valence changes associated with the metal-insulator transition in Bi${}_{1-x}$La${}_x$NiO${}_3$
• Unusual Mott transition associated with charge-order melting in BiNiO${}_3$ under pressure
• Phase transitions in the Hubbard model for the bismuth nickelate
• V 3$d$ charge and orbital states in V${}_2$OPO${}_4$ probed by x-ray absorption spectroscopy
• Mechanism of intermetallic charge transfer and bond disproportionation in BiNiO${}_3$ and PbNiO${}_3$ revealed by hard x-ray photoemission spectroscopy
• Orthorhombic phase of La${}_{0.5}$Bi${}_{0.5}$NiO${}_3$ studied by first principles
• Mass enhancement and metal-nonmetal transition driven by d-f hybridization in perovskites La1-xPrxCuO3