Band filling versus bond bending in substituted LxSr2-xFeMoO6 (L=Ca, La, Nd) compounds

D. RUBI; C. FRONTERA; G. HERRANZ; J.L. GARCÍA MUÑOZ; C. RITTER; J. FONTCUBERTA

Anaheim, USA

Congreso; 9th Joint Magnetism and Magnetic Materials (MMM)/Intermag Conference; 2004

With the aim of determining and discriminating the influence of both steric and band-filling effectson the strength of the magnetic interactions of double perovskites, we have studied the structural and magnetic properties of substituted LxSr2-2xFeMoO6 (L=Ca, La, and Nd) compounds. Our results show that the raising of Curie temperature in electron-doped samples (La and Nd substitutions) is mainly due to band-filling effects, being that the influence of structural distortions (steric effects) is of less relevance. This fact contrasts with the well-known properties of manganites, where a strong correlation between structural properties and magnetic interactions is present. We argue that this disagreement relies on the different symmetries of the electronic orbitals involved in the magnetic interactions in both cases.