Anomalous Pr ordering and the systematic variation of(Pr) for the Hg-1212-type systems

C. Chou, Y. Hsu, J. Shieh, T. Lee, H. Ku, J. Ho

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Structural, magnetic, and calorimetric studies have been made to reveal an anomalous Pr antiferromagnetic ordering at (Formula presented)(Pr) of 6 K in (Formula presented)(Formula presented)(Formula presented). This compound has the Hg-1212-type tetragonal structure with lattice parameters a=3.8532 Å and c=12.1199 Å. X-ray Rietveld refinement yields a Pr-O bond length d(Pr-O) of 2.492 Å between Pr and oxygen in the adjacent (Formula presented) layers and an O-Pr-O bond angle of 101.3°. The low-temperature magnetic entropy associated with the Pr ordering is only about 10% of Rln3 expected for (Formula presented) with a quasitriplet ground state, suggesting a more two-dimensional-like ordering process. This result supports the earlier observation of a systematic dependence of (Formula presented)(Pr) on Pr-O bond length in various M(Ba, Sr(Formula presented)(Formula presented)(Formula presented) (M=Cu, Hg, Tl, Pb) 1212-type Pr compounds. This in turn points to the importance of a superexchange magnetic coupling mechanism.

Original languageEnglish
Pages (from-to)6729-6733
Number of pages5
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume53
Issue number10
DOIs
Publication statusPublished - 1996 Jan 1
Externally publishedYes

    Fingerprint

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this