Crystal Field effect on the effective magnetic moment in A2CoWO6 (A = Ca, Sr and Ba)

C.A. LÓPEZ; M.E. SALETA; J .CURIALE; R.D. SÁNCHEZ

MATERIALS RESEARCH BULLETIN

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2012 vol. 47 p. 1158 - 1163

0025-5408

We prepared the antiferromagnetic Ca2CoWO6, Sr2CoWO6 and Ba2CoWO6 double perovskites with different crystalline structures, which are monoclinic, tetragonal and cubic respectively. The crystalline structures affect the Co-O distances and the local octahedral symmetry. Magnetic susceptibility experiments were performed as a function of magnetic field and temperature. We found that the effective magnetic moment (μeff ) of Co2+ is partially unquenched and we also found that μeff increases with the average of Co-O distances that form the CoO6 octahedra. A simple model associates the behavior of the effective magnetic moment with crystal field effects.