Abstract :
New multi-component perovskite-type oxides CaCu3V4−xMnxO12 with 0.5≤x≤2.0 have been synthesized at high pressures (P=8.0–9.0 GPa) and high temperatures (T=1000–1300 °C). Their crystal structure and grain sizes were evaluated by X-ray diffraction and scanning electron microscopy, respectively. Using ab initio calculations we studied the electronic and magnetic properties of CaCu3V3MnO12 and CaCu3V2Mn2O12 in comparison with CaCu3V4O12 and CaCu3Mn4O12. Within the GGA+U approximation, a phase transition from ferrimagnetic half-metal to ferrimagnetic semiconductor was predicted for CaCu3V4−xMnxO12 with increasing manganese concentration. The magnetic couplings for CuV and CuMn are antiferromagnetic, while MnMn, CuCu, and CuV are coupled ferromagnetically.
