Orbital Configurations and Magnetic Properties of Double-Layered Antiferromagnet Cs<SUB>3</SUB>Cu<SUB>2</SUB>Cl<SUB>4</SUB>Br<SUB>3</SUB>

• Yamada Fumiko

  Department of Physics, Tokyo Institute of Technology

• Ono Toshio

  Department of Physics, Tokyo Institute of Technology

• Tanaka Hidekazu

  Department of Physics, Tokyo Institute of Technology

• Yamaura Jun-ichi

  Institute for Solid State Physics, The University of Tokyo

Bibliographic Information

Other Title

• Orbital Configurations and Magnetic Properties of Double-Layered Antiferromagnet Cs3Cu2Cl4Br3

Abstract

We report the single-crystal X-ray analysis and magnetic properties of a new double-layered perovskite antiferromagnet, Cs₃Cu₂Cl₄Br₃. This structure is composed of Cu₂Cl₄Br₃ double layers with elongated CuCl₄Br₂ octahedra and is closely related to the Sr₃Ti₂O₇ structure. An as-grown crystal has a singlet ground state with a large excitation gap of Δ⁄k_B\\simeq2000 K, due to the strong antiferromagnetic interaction between the two layers. Cs₃Cu₂Cl₄Br₃ undergoes a structural phase transition at T_s\\simeq330 K accompanied by changes in the orbital configurations of Cu²⁺ ions. Once a Cs₃Cu₂Cl₄Br₃ crystal is heated above T_s, its magnetic susceptibility obeys the Curie–Weiss law with decreasing temperature even below T_s and does not exhibit anomalies at T_s. This implies that in the heated crystal, the orbital state of the high-temperature phase remains unchanged below T_s, and thus, this orbital state is the metastable state. The structural phase transition at T_s is characterized as an order–disorder transition of Cu²⁺ orbitals.

Journal

• Journal of the Physical Society of Japan

  Journal of the Physical Society of Japan 76 (1), 014708-014708, 2007

  THE PHYSICAL SOCIETY OF JAPAN

Keywords

• Cs<SUB>3</SUB>Cu<SUB>2</SUB>Cl<SUB>4</SUB>Br<SUB>3</SUB>
• double-layered perovskite
• Sr<SUB>3</SUB>Ti<SUB>2</SUB>O<SUB>7</SUB> structure
• Jahn–Teller effect
• singlet ground state
• structural phase transition
• orbital order and disorder

Details

• CRID: 1390001204195941760
• NII Article ID: 130005296480
• NII Article ID: 110006151558
• NII Article ID: 210000106504
• NII Book ID: AA00704814
• DOI: 10.1143/jpsj.76.014708
• ISSN: 13474073
• ISSN: 00319015
• NDL BIB ID: 8606112
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8606112
• Web Site: http://journals.jps.jp/doi/pdf/10.1143/JPSJ.76.014708
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed