R-site cation randomness effect in the A-site ordered Y_(0.5)La_(0.5)BaMn_2O_6 compound  

作　　者：高庆庆 李静波 李冠男 饶光辉 骆军 刘广耀 梁敬魁 

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences [2]School of Materials Science and Engineering,Beijing Institute of Technology [3]School of Materials Science and Engineering,Guilin University of Electronic Technology

出　　处：《Chinese Physics B》2013年第7期499-502,共4页中国物理B（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.50872148,51072225,and 11074295);the Natural Science Foundation of Guangxi Province,China(Grant No.2012GXNSFGA060002)

摘　　要：The R/Ba-ordered and R-site mixed compound Y0.5La0.5BaMn2O6 is synthesized, in which （Y, La） and Ba are regularly arranged, while Y and La randomly occupy the R-site. Y0.5La0.5BaMn2O6 has a tetragonal unit cell with a space group of P4/mmm. A structural transition between tetragonal and orthorhombic is observed at about 325 K by X-ray powder diffraction （XRD）. Thermal magnetic measurement shows the occurrence of an antiferromagnetic transition at the temperature TN～190 K. Anomalies in magnetization, resistivity and lattice parameters observed around 340 K indicate a charge/orbital order transition accompanying the structural phase transition. The R-site randomness effect is discussed to interpret the different properties of Y0.5La0.5BaMn2O6 between NdBaMn2O6 and SmBaMn2O6.The R/Ba-ordered and R-site mixed compound Y0.5La0.5BaMn2O6 is synthesized, in which （Y, La） and Ba are regularly arranged, while Y and La randomly occupy the R-site. Y0.5La0.5BaMn2O6 has a tetragonal unit cell with a space group of P4/mmm. A structural transition between tetragonal and orthorhombic is observed at about 325 K by X-ray powder diffraction （XRD）. Thermal magnetic measurement shows the occurrence of an antiferromagnetic transition at the temperature TN～190 K. Anomalies in magnetization, resistivity and lattice parameters observed around 340 K indicate a charge/orbital order transition accompanying the structural phase transition. The R-site randomness effect is discussed to interpret the different properties of Y0.5La0.5BaMn2O6 between NdBaMn2O6 and SmBaMn2O6.

关 键 词：A-site ordering structural transition charge/orbital ordering X-ray powder diffraction 

分 类 号：O469[理学—凝聚态物理]