Structural phase transition and magnetic properties of double perovskites Ba2CaMO6 (M=W, Re, Os)

✍ Scribed by Kazuhiro Yamamura; Makoto Wakeshima; Yukio Hinatsu

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 380 KB
• Volume: 179
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2005.10.003

✦ Synopsis

Structures and magnetic properties for double perovskites Ba 2 CaMO 6 (M ¼ W, Re, Os) were investigated. Both Ba 2 CaReO 6 and Ba 2 CaWO 6 show structural phase transitions at low temperatures. For Ba 2 CaReO 6 , the second order transition from cubic Fm 3 m to tetragonal I4/m has been observed near 120 K. For Ba 2 CaWO 6 , the space group of the crystal structure is I4/m at 295 K and the transition to monoclinic I2/m has been observed between 220 K. Magnetic susceptibility measurements show that Ba 2 CaReO 6 (S ¼ 1=2) and Ba 2 CaOsO 6 (S ¼ 1) transform to an antiferromagnetic state below 15.4 and 51 K, respectively. Anomalies corresponding to their structural phase transition and magnetic transition have been also observed through specific heat measurements.