Eur. Phys. J. B 4, 159-167 (1998)
https://doi.org/10.1007/s100510050364

Charge states of transition metal in "Cr, Co and Ni" doped Ln_0.5Ca_0.5MnO₃ CMR manganites

Laboratoire CRISMAT (UMR 6508) , associée au CNRS, ISMRA, boulevard Maréchal Juin, 14050 Caen Cedex, France

Corresponding author: ^a studer@crindy.ismra.fr

Received: 9 January 1998
Revised: 6 April 1998
Accepted: 7 April 1998
Published online: 15 July 1998

Abstract

The XAS study at Cr, Co, Ni and Mn K-edges was performed for the doped CMR manganites Ln_0.5Ca_0.5Mn₁-_xB_xO₃ with Ln=La, Nd, Sm and B= Cr, Co, Ni (0 ≤_x≤0.10), on the samples that were studied previously for their ferromagnetic-metallic to antiferromagnetic-insulator transition. We observed that the formal charges of the doping elements are Ni²⁺, Co²⁺ and Cr³⁺. It is also evidenced that the average formal charge of the manganese is increased after doping, in agreement with the charge compensation keeping "O₃" stoichiometry. These results suggest that the doping elements participate directly to the band structure.