摘要
The fact that there are Mn^(2+) at the A sites in the ABO_3 perovskite phase of manganites with the nominal composition La_(0.6-x)Nd_xSr_(0.1)MnO_3 showed by detailed experimental study and theoretical calculations.The magnetic moments of these Mn^(2+) are antiparallel to those of the Mn ions at the B sites.The content of the Mn^(2+) increases as the average ionic radius,<r_A>,of the ions at A sites decreases,resulting in the experimentally observed phenomenon that the content of the Mn_3O_4 phase in the manganites decreases with decreasing <r_A>.
基金
supported by the National Natural Science Foundation of China (No. NSF-11174069)
the Natural Science Foundation of Hebei Province (No.E2011205083)
the Key Item Science Foundation of Hebei Province (No. 10965125D)
the Key Item Science Foundation of Education Department of Hebei Province (No.ZD2010129)
the National High Technology Research and Development Program of China (863 Program,No.2007AA03Z100)
