Coupling between electronic and structural degrees of freedom in the triangular lattice conductor NaxCoO2

Abstract

The determination by powder neutron diffraction of the ambient temperature crystal structures of compounds in the NaxCoO2 family, for 0.3 < x <= 1.0, is reported. The structures consist of triangular CoO2 layers with Na ions distributed in intervening charge reservoir layers. The shapes of the CoO6 octahedra that make up the CoO2 layers are found to be critically dependent on the electron count and on the distribution of the Na ions in the intervening layers, where two types of Na sites are available. Correlation of the shapes of cobalt-oxygen octahedra, the Na ion positions, and the electronic phase diagram in NaxCoO2 is made, showing how structural and electronic degrees of freedom can be coupled in electrically conducting triangular lattice systems.

15 pages, 1 tables, 6 figures Submitted to Physical Review B

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Cited by in corpus (46)

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• Magnetic ordering and spin waves in $\mathbf{N}{\mathbf{a}}_{0.82}\mathbf{Co}{\mathbf{O}}_2$
• Crystal Structure and Elementary Properties of NaxCoO2 (x = 0.32, 0.5, 0.6, 0.75, and 0.92) in the Three-Layer NaCoO2 Family
• Theory of Sodium Ordering in NaxCoO2
• Three-Dimensional Spin Fluctuations in Na0.75CoO2
• Series of Bulk Magnetic Phase Transitions in NaxCoO2: a muSR study
• Low-lying quasiparticle states and hidden collective charge instabilities in parent cobaltate superconductors (NaxCoO2)
• 1D to 2D Na Ion Diffusion Inherently Linked to Structural Transitions in Na${}_{0.7}$CoO${}_2$
• The intercalation chemistry of layered iron chalcogenide superconductors
• Evidence of a single nonmagnetic Co3+ state in the Na1CoO2 cobaltate
• Disproportionation Transition at Critical Interaction Strength: Na${}_{1/2}$CoO${}_2$
• Non-magnetic insulator state in Na1CoO2 and phase separation of Na vacancies
• NQR and X-ray investigation of the structure of Na${}_{2/3}$CoO${}_2$ compound
• Direct link between low temperature magnetism and high temperature sodium order in NaxCoO2
• Discontinuous Lifshitz Transition Achieved by Band-Filling Control in NaxCoO2
• Destruction of the small Fermi surfaces in Na${}_x$CoO${}_2$ by Na disorder
• Anisotropic quasiparticle renormalization in Na0.73CoO2: role of inter-orbital interactions and magnetic correlations
• Elliptical hole pockets in the Fermi surfaces of unhydrated and hydrated sodium cobalt oxides
• Melting of the Na layers in solid Na0.8CoO2
• Stoichiometric oxygen content in NaxCoO2
• Electronic structure of the $\mathrm{C}{\mathrm{a}}_3\mathrm{C}{\mathrm{o}}_4{\mathrm{O}}_9$ compound from ab initio local interactions
• Polarization dependence of x-ray absorption spectra in Na_xCoO_2
• Electronic phase diagram of LixCoO2 revisited with potentiostatically de-intercalated single crystals
• Infrared Conductivity and Charge Ordering in NaCoO2
• Theoretical analysis of oxygen vacancies in layered sodium cobaltate Na_xCoO_{2-δ}
• Sodium Trimer Ordering on NaxCoO2 Surface
• Itinerant and localized magnetism on the triangular lattice: sodium rich phases of Na${}_x$CoO${}_2$
• Rearrangement of Sodium ordering and its effect on physical properties in $N{a}_{x}Co{O}_2$ system
• Quantification of Coulomb Interactions in layered Lithium and Sodium Battery Cathode Materials
• Localized versus itinerant magnetic moments in Na0.72CoO2
• Spin fluctuations, magnetic long-range order and Fermi surface gapping in NaxCoO2
• Fabrication and Low Temperature Thermoelectric Properties of Na_xCoO_2 (x = 0.68 and 0.75) Epitaxial Films by the Reactive Solid-Phase Epitaxy
• Magnetic Phase Transition at 88 K in Na0.5CoO2 revealed by 23Na-NMR investigations
• Phonon study of Jahn-Teller distortion and phase stability in NaMnO${}_2$ for sodium-ion batteries
• Search for Magnetic Excitation Spectra of NaxCoO2.yD2O -Neutron Scattering-
• Synthesis of sodium cobaltate Na${}_x$CoO${}_2$ single crystals with controlled Na ordering
• Magnetic, electrochemical and thermoelectric properties of $P2-N{a}_x(C{o}_{7/8}S{b}_{1/8})O_2$
• New electronic orderings observed in cobaltates under the influence of misfit periodicities
• Comment on "Raman spectroscopy study of NaxCoO2 and superconducting NaxCoO2 yH2O"
• Chemical tuning between triangular and honeycomb structures in a 5$d$ spin-orbit Mott insulator
• The magnetic field and pressure dependence of the magnetic ordering transition in NaxCoO2 (0.6<x<0.72)
• A possibility of high spin hole states in doped CoO${}_2$ layered systems
• Sodium ion ordering of Na0.77CoO2 under competing multi-vacancy cluster, superlattice and domain formation
• Temperature-driven sodium-ion dynamical-to-static crossover in the zig-zag ordered phase of Na${}_{0.5}$CoO${}_2$