Electron and hole doping effects in Sr2FeMoO6 double perovskites

Electron and hole doping effects in the ferromagnetic and structural properties of the double perovskite Sr2FeMoO6 are studied along the series Sr-2 xLaxFeMoO6 (0 less than or equal to x less than or equal to 1) and Sr2-xFeMoO6 (0 less than or equal to x less than or equal to 0.4) from neutron powder diffraction and magnetization data. Sr-deficient samples (hole doped) show moderate changes in the structure and both T-c and M-s rapidly decrease with x. On the contrary, a change from tetragonal to monoclinic symmetry and a non monotonic behaviour in T-c is found in the La-substittited series (electron doped). (C) 2003 Elsevier B.V. All rights reserved.