Influence of Magnetic Gd 3+ Ion on the Intensity of Mn 4+ R-Line in Oxides with Perovskite Structures

The purpose of this paper is to show that the Mn 4+ 2 E → 4 A 2 spin forbidden emission transition (R-line) is intensified in Gd 3+ based compounds with the perovskite ABO 3 and double perovskite A 2 BB’O 6 structures. The intensity of the R-line is compared in compounds with non-magnetic ions such as Y, La and Eu. and those with Gd ion. The significant increase in the intensity of the spin forbidden transition is explained by a simple model of exchange coupling in the dimeric unit, Mn 4+ −O 2− −Gd 3+ . It is also pointed out that exchange interaction between the Mn 4+ and Gd 3+ ions cause significant broadening of the R-line in compound having the pyrochlore structure.