Structural instabilities of infinite-layer nickelates from first-principles simulations

Abstract

Rare-earth nickelates RNiO${}_2$ adopting an infinite-layer phase show superconductivity once La, Pr or Nd are substituted by a divalent cation. Either in the pristine or doped form, these materials are reported to adopt a high symmetry, perfectly symmetric, P4/mmm tetragonal cell. Nevertheless, bulk compounds are scarce, hindering a full understanding of the role of chemical pressure or strain on lattice distortions that in turn could alter magnetic and electronic properties of the 2D nickelates. Here, by performing a full analysis of the prototypical YNiO${}_2$ compound with first-principles simulations, we identify that these materials are prone to exhibit O${}_4$ group rotations whose type and amplitude are governed by the usual R-to-Ni cation size mismatch. We further show that these rotations can be easily tuned by external stimuli modifying lattice parameters such as pressure or strain. Finally, we reveal that H intercalation is favored for any infinite-layer nickelate member and pushes the propensity of the compounds to exhibit octahedra rotations.

References in corpus (13)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• A superconducting praseodymium nickelate with infinite layer structure
• Nickelate superconductivity without rare-earth magnetism: (La,Sr)NiO${}_2$
• Superconductivity in infinite-layer nickelate La${}_{1-x}$Ca${}_x$NiO${}_2$ thin films
• Role of $4f$ states in infinite-layer NdNiO${}_2$
• Mott gapping in 3d ABO3 perovskites without Mott-Hubbard interelectronic U
• Topotactic transformation of single-crystals: from perovskite to infinite-layer nickelates
• Universal spin-glass behaviour in bulk LaNiO2, PrNiO2 and NdNiO2
• Bulk NdNiO2 is thermodynamically unstable with respect to decomposition while hydrogenation reduces the instability and transforms it from metal to insulator
• Origin of the orbital and spin orderings in rare-earth titanates
• First-principles study of electron and hole doping in perovskite nickelates
• Dynamical structural instability and its implication on the physical properties of infinite-layer nickelates

Cited by in corpus (5)

• Synthesis and physical properties of LaNiO${}_2$ crystals
• Investigation of hydrogen incorporations in bulk infinite-layer nickelates
• Possible structural quantum criticality tuned by rare-earth ion substitution in infinite-layer nickelates
• Electron-phonon mediated superconductivity in La${}_6$Ni${}_5$O${}_{12}$ nickel oxides
• Lattice dynamics of the infinite-layer nickelate LaNiO${}_2$