Crystal structures and magnetic properties of ordered perovskites A2R3+Ir5+O6 (A=Sr, Ba; R=Sc, Y, La, Lu)

Abstract

Abstract The ordered perovskite-type compounds A 2 RIrO 6 (A=Sr, Ba; R=Sc, Y, Lu, La), with the exception of Sr 2 LaIrO 6 , were prepared. Using the Rietveld method, their crystal structures were assigned to be monoclinic (space group P2 1 /n ) with a fully ordered arrangement between R and Ir ions. For Sr 2 ScIrO 6 and Ba 2 ScIrO 6 , small amounts of disordered arrangements between Sc and Ir ions were found. The magnetic susceptibilities of these compounds show paramagnetic behavior down to 4.5 K. The magnetic behavior for these compounds is explained by Kotani’s theory and the spin–orbit coupling constants for the Ir(V) ion were calculated.