| Popis: |
The synthesis, structure and magnetic properties of the double perovskites Sr2-xCaxFeOsO6 (x=0.1-0.9) are reported. X-ray and neutron diffraction measurements show a transition from a monoclinic P21/n symmetry to a tetragonal I4/m symmetry with increasing strontium content. Magnetic measurements show ferrimagnetism present in the compounds with x= 0.1-0.5 with Curie temperatures ranging from 150-200K. The magnetism of these compounds saturate at 7 T with a magnetization of about 1.8 µB/f.u.. The compounds with x= 0.5-0.3 exhibit a decrease in saturation magnetization with increasing strontium content, indicating a loss of ferrimagnetism with finally exhibiting an antiferromagnetic behavior in the x= 0.1 sample. Neutron diffraction measurements of the x= 0.3 and 0.4 samples show that even as the compound transitions to an antiferromagnet, it exhibits some amount of ferrimagnetism, suggesting the presence of an inhomogeneous phase separation at the x=0.3-0.4 range. |
