Mössbauer investigation of 57Fe-doped TlSr2CoO5

✍ Scribed by Jean-Pierre Doumerc; Martine Coutanceau; Leopold Fournés; Jean-Claude Grenier; Michel Pouchard; Alain Wattiaux

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 640 KB
• Volume: 2
• Category: Article
• ISSN: 1387-1609
• DOI: 10.1016/s1387-1609(00)88577-1

✦ Synopsis

The thallium cobaltite TlSr,CoO, undergoes a metal-insulator transition near room temperature. Mossbauer investigation of a 57Fe-doped sample shows that iron actually enters into the lattice and that a long range antiferromagnetic order sets in below 150 K explaining the origin of a peak previously observed in the temperature dependence of the magnetic susceptibility. An unexpected complex behaviour is found for the high temperature phase for which previous electron diffraction and X-ray diffraction studies revealed a single site for Co atoms. The results are interpreted in terms of a dynamical formation of two types of structural domains characterized by a fluctuation of Co-O bond lengths inducing a fluctuation of Co spin state. 0 1999 AcadCmie des sciences I Editions scientifiques et medicales Elsevier SAS.