Alkaline earth doping in lanthanum neodymium calcium cuprates with the "212" structure

D. H. Gregory, M. T. Weller, C. V.N. Rao, D. B. Currie

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The solid solutions La1-xNdSrxCaCu2Oy (0 ≤ x ≤ 0.6) and La1-xNdCa1+xCu2Oy (0 ≤ x ≤ 0.5) were synthesised by conventional solid state reaction methods. All compounds were subsequently annealed at high oxygen pressures (≈ 450atm). Both series of materials have been characterised by powder x-ray diffraction and oxygen stoichiometries for unannealed and high pressure annealed samples were determined by thermogravimetric analysis. Structures of two of the unannealed calcium doped series (x = 0 and x = 0.4) were determined by Rietveld analysis of powder x-ray diffraction data. Structural studies showed low oxygen levels, y < 6, and that the O3 site between Cu-1bO planes is vacant. The structures also showed increasing Cu-1bCu interplanar distance with increasing calcium content. Resistivity measurements showed no superconducting transitions in these materials. Structural aspects of these and other 212 phases are discussed in relation to the observation or absence of superconducting behaviour.

Original languageEnglish
Pages (from-to)1309-1318
Number of pages10
JournalMaterials Research Bulletin
Volume27
Issue number11
DOIs
Publication statusPublished - Nov 1992
Externally publishedYes

Fingerprint

Neodymium
Lanthanum
neodymium
lanthanum
cuprates
calcium
Calcium
x ray diffraction
Earth (planet)
Doping (additives)
Oxygen
high pressure oxygen
Powders
oxygen
Diffraction
Rietveld analysis
stoichiometry
X rays
solid solutions
solid state

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Alkaline earth doping in lanthanum neodymium calcium cuprates with the "212" structure. / Gregory, D. H.; Weller, M. T.; Rao, C. V.N.; Currie, D. B.

In: Materials Research Bulletin, Vol. 27, No. 11, 11.1992, p. 1309-1318.

Research output: Contribution to journalArticle

Gregory, D. H. ; Weller, M. T. ; Rao, C. V.N. ; Currie, D. B. / Alkaline earth doping in lanthanum neodymium calcium cuprates with the "212" structure. In: Materials Research Bulletin. 1992 ; Vol. 27, No. 11. pp. 1309-1318.
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