Source zotero
Authors Junjie Zhang, Hong Zheng, Yu-Sheng Chen, Yang Ren, Masao Yonemura, Ashfia Huq, J. F. Mitchell
arXiv / Publisher https://link.aps.org/doi/10.1103/PhysRevMaterials.4.083402
PDF Not available in this batch.
Relevance score Not available in this batch.
Primary category Not available in this batch.
Published 2020-08-12
Research paradigm Unknown
Sample form Unknown

Summary

High oxygen pressure floating zone growth and crystal structure of the metallic nickelates R4Ni3O10 ( R = La, Pr )

Materials

Not available in this batch.

Methods

Not available in this batch.

Keywords

Not available in this batch.

Highlights

Not available in this batch.

Conclusions

Not available in this batch.

Main claims

  • The room-temperature thermodynamic phase of R4Ni3O10 (R=La, Pr) is monoclinic P21/a (Z=2); a metastable orthorhombic Bmab phase can be trapped by rapid cooling.
    • Evidence: Synchrotron single-crystal XRD unambiguously solves both structures,Annealing biphasic samples converts Bmab to P21/a,Different MMT temperatures correspond to the two phases
  • The metal-to-metal transition (MMT) is accompanied by a weak lattice response and differs by ≈10 K between the two La4Ni3O10 phases.
    • Evidence: Temperature-dependent XRD shows anomalies in lattice parameters at the MMT,Resistivity, susceptibility, and heat capacity all show sharp anomalies at the respective T_MMT

Workflow

  • high_o2_crystal_growth — High-quality single crystals of R4Ni3O10 grown.
    • Materials: Polycrystalline R4Ni3O10 rods (R=La, Pr)
    • Methods: High-pressure optical-image floating zone (SciDre HKZ); O2 pressures: 20 bar (La), 140 bar (Pr); Xe arc lamp (3-5 kW)
    • Observations: La4Ni3O10 boule with shiny facets; single crystals up to 4.5 mm; Synchrotron XRD confirms large single crystal region; Oxygen content 9.98(1) for La, 10.05(1) for Pr
  • structure_determination — Crystal structures established: P21/a (Z=2) is the thermodynamic phase.
    • Materials: R4Ni3O10 single crystals
    • Methods: Synchrotron and lab single-crystal XRD; Neutron powder diffraction; Rietveld refinement
    • Observations: La4Ni3O10: Bmab (fast cooling) and P21/a (slow cooling) identified; Pr4Ni3O10: onlyP21/a; Lattice anomalies at MMT
  • physical_property_measurements — Physical properties confirm metal-to-metal transitions.
    • Materials: Oriented single crystals
    • Methods: Resistivity (four/six-terminal); Magnetic susceptibility (SQUID); Heat capacity (PPMS)
    • Observations: MMT at 138.6 K (P21/a La4Ni3O10), 147.5 K (Bmab La4Ni3O10), 157.6 K (Pr4Ni3O10); Anisotropic resistivity and susceptibility; γ ≈13-14.5 mJ/(mol K2)