Structural phase transition and magnetic properties of double perovskites Ba2CaMO6 (M=W, Re, Os)
Structural phase transition and magnetic properties of double perovskites Ba2CaMO6 (M=W, Re, Os)
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DOI：
10.1016/j.jssc.2005.10.003
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发表时间：
2006-03
影响因子：
3.3
通讯作者：
K. Yamamura;M. Wakeshima;Y. Hinatsu
中科院分区：
文献类型：
--
作者：
K. Yamamura;M. Wakeshima;Y. Hinatsu
研究了双钙钛矿Ba 2CaMO 6（M=W，Re，Os）的结构和磁性。Ba_2CaReO_6和Ba_2CaWO_6在低温下都表现出结构相变。对于Ba 2CaReO 6，在120 K附近观察到从立方Fm 3 ⁄ m到四方I4/m的二级转变。Ba_2CaWO_6晶体在295 K时空间群为I_4/m，在220 K时发生了向单斜I_2/m的转变。磁化率测量表明，Ba 2CaReO 6（S=1/2）和Ba 2CaOsO 6（S=1）在15.4和51 K以下分别转变为反铁磁态。通过比热测量也观察到了与结构相变和磁相变相对应的反常现象。
Structures and magnetic properties for double perovskites Ba2CaMO6(M=W, Re, Os) were investigated. Both Ba2CaReO6and Ba2CaWO6show structural phase transitions at low temperatures. For Ba2CaReO6, the second order transition from cubic Fm3¯m to tetragonal I4/m has been observed near 120K. For Ba2CaWO6, the space group of the crystal structure is I4/m at 295K and the transition to monoclinic I2/m has been observed between 220K. Magnetic susceptibility measurements show that Ba2CaReO6(S=1/2) and Ba2CaOsO6(S=1) transform to an antiferromagnetic state below 15.4 and 51K, respectively. Anomalies corresponding to their structural phase transition and magnetic transition have been also observed through specific heat measurements.