[摘要]：Synthesis and magnetic properties of nanocrystals (size similar or equal to 22 nm) of cubic spinel MgMnO3 with the defect structure [Mg2+][Mg1/32+Mn4/34+square(1/3)]O-4 are reported. Analysis of the magnetization M versus T (2-370 K) and M versus H (up to 65 kOe) data shows a blocking temperature T-B similar or equal to 11 K and an estimated Neel temperature T-N similar to 150 K above which the Weiss temperature theta=-7 K and mu=3.91 mu(B)/Mn4+. For T-B < T < T-N, fit of the M versus H data to modified Langevin function yields 35 mu(B) as magnetic moment/particle, resulting from the defect structure. (c) 2010 American Institute of Physics. [doi:10.1063/1.3489094]
