Synthesis, crystal structure, electrical, and magnetic properties of the new layered cobalt oxides (Sr, Ca, Ln)3Co2O6±δ (Ln = Sm, Eu, Gd, Tb, Dy, Ho, and Y)

K. Yamaura, Q. Huang, R. J. Cava

Research output: Contribution to journalArticlepeer-review

31 Scopus citations

Abstract

New layered Co oxides of nominal formula Sr2(Ln0.8Ca0.2) Co2O6 (Ln = Sm, Eu, Gd, Tb, Dy, Ho, and Y) are reported. Single-phase polycrystalline samples were obtained at compositions Sr2Y1-xCaxCo2.5+ 2O6-δ (0.2 ≤ x ≤ 0.5; 0 ≤ δ ≤ 0.24), Sr2Y1-xCaxCo3.4+2O 6+δ′ (0.2 ≤ x ≤ 0.5; 0.62 ≤ δ′ ≤ 0.79), and Sr2Dy0.8Ca0.2Co2O6.09. Powder X-ray and neutron diffraction, thermogravimetric analysis, magnetic susceptibility, and ac resistivity measurements were used to characterize the samples. The tetragonal unit cell for Sr2Y0.8Ca0.2Co2O6.00 (I4/mmm; a = 3.82765(6) Å, and c = 19.5795(3) Å) is comparable to that of the double layer superconducting copper oxide La2-xSrxCaCu2 O6. A long-range antiferromagnetic (AF) ordered state below about 300 K is found for Sr2Y1-xCaxCo2.5+2O 6-δ, and a magnetically glassy state below about 40 K for the oxidized AF phases. All materials are electrically insulating.

Original languageEnglish (US)
Pages (from-to)277-286
Number of pages10
JournalJournal of Solid State Chemistry
Volume146
Issue number1
DOIs
StatePublished - Aug 1999

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Inorganic Chemistry
  • Materials Chemistry

Keywords

  • Kohlrausch law
  • LaSrCaCuO
  • Layered structure
  • Spin glass
  • Sr(Ln, Ca)CoO

Fingerprint Dive into the research topics of 'Synthesis, crystal structure, electrical, and magnetic properties of the new layered cobalt oxides (Sr, Ca, Ln)<sub>3</sub>Co<sub>2</sub>O<sub>6±δ</sub> (Ln = Sm, Eu, Gd, Tb, Dy, Ho, and Y)'. Together they form a unique fingerprint.

Cite this