High-pressure Synthesis of Ba2CoO2Ag2Te2with Extended CoO2Planes

Yuki Matsumoto, Yusuke Nambu, Takashi Honda, Kazutaka Ikeda, Toshiya Otomo, Hiroshi Kageyama

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


Using a high-pressure synthesis method, we prepared the layered oxychalcogenide Ba2CoO2Ag2Te2 (space group: I4/mmm) with alternating stacks of CoO2 and Ag2Te2 layers, separated by Ba atoms. The CoO2 plane is greatly extended (Co-O = 2.19 Å on average) due to tensile strain from adjacent Ag2Te2 layers, causing displacement of oxide anions. Layered cobaltates with trans-CoO4X2 (X = chalcogen, halogen) coordination feature large spin-orbit coupling, which is linearly scaled by the tetrahedral factor of dCo-X/dCo-O. However, applying this relation to Ba2CoO2Ag2Te2 yields a magnetic moment of ∼4 μB, which is nearly twice the experimentally observed value of 1.87(17) μB. This result, along with a reduced Néel temperature (TN = 60 K), originates from the off-centered position of otherwise under-bonded oxide anions, which changes the crystal field splitting of Co d orbitals.

Original languageEnglish
Pages (from-to)8121-8126
Number of pages6
JournalInorganic chemistry
Issue number12
Publication statusPublished - 2020 Jun 15

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry


Dive into the research topics of 'High-pressure Synthesis of Ba2CoO2Ag2Te2with Extended CoO2Planes'. Together they form a unique fingerprint.

Cite this