%0 Journal Article
%T Formation mechanism, optical and magneto-dielectric studies of new cubic spinel MgMnO3
%A S. Thota
%A K. Singh
%A B. Prasad
%A J. Kumar
%J AIP Advances
%D 2012
%I AIP Publishing LLC
%R 10.1063/1.4747457
%X The formation mechanism, phase stability, optical and magnetodielectric properties of new cubic MgMnO3 bulk and nano-crystals are reported. The diffuse reflectance spectroscopy of this compound shows a ligand-to-metal charge transfer transition p[O2 ]¡úeg[Mg2+] at 4 eV and the lowest spin allowed metal-to-metal transition at 2.43 eV. In bulk MgMnO3 with the defect cubic structure [Mg2+][Mg2+1/3Mn4+4/3¡õ1/3]O4 (Seehra Appl. Phys. Lett. 97, 112507 (2010)10.1063/1.3489094) a clear change in the dielectric constant ( ¡ä) is observed on cooling through its blocking temperature TB ¡«17.5 K. This dielectric anomaly is magnetic field independent even at 14 kOe. A clear evidence of the magneto-dielectric effect is observed for T < TB. Possible origin of the magneto-dielectric coupling has been discussed.
%U http://link.aip.org/link/doi/10.1063/1.4747457