Ca25Co22O56(OH)28: A layered misfit compound

T. Klimczuk, H. W. Zandbergen, N. M. van der Pers, L. Viciu, V. L. Miller, M. H. Lee, R. J. Cava

Research output: Contribution to journalArticlepeer-review

5 Scopus citations


The high pressure synthesis, structure and magnetic properties of Ca25Co22O56(OH)28 are reported. The compound has a misfit structure, consisting of double, square calcium oxide hydroxide rock-salt-like layers between hexagonal CoO2 layers. The misfit compound crystallizes in the monoclinic space group C2/m, and can be characterized by the coexistence of two subsystems with common a = 4.893(5) Å, c = 8.825(9) Å and β = 95.745(8) parameters, and different b parameters: bRS = 4.894(5) Å, and bHEX = 2.809(3) Å, for the rock-salt and hexagonal type planes, respectively. The compound shows Curie-Weiss paramagnetism with an antiferromagnetic Weiss temperature of -43 K and a reduced Co moment. Substantial deviations from Curie-Weiss behavior are seen below 50 K with no indication of magnetic ordering. No superconductivity was observed down to a temperature of 2 K.

Original languageEnglish (US)
Pages (from-to)1673-1680
Number of pages8
JournalMaterials Research Bulletin
Issue number9
StatePublished - Sep 14 2006

All Science Journal Classification (ASJC) codes

  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


  • A. Oxides
  • B. Chemical synthesis
  • C. Electron diffraction
  • C. X-ray diffraction


Dive into the research topics of 'Ca25Co22O56(OH)28: A layered misfit compound'. Together they form a unique fingerprint.

Cite this