Electronic Structure, Mechanical and Magnetic Properties of the Quaternary Perovskites CaA3V4O12 (A = Mn, Fe, Co, Ni and Cu)

Quaternary perovskites CaA3V4O12 (A = Mn, Fe, Co, Ni and Cu) have been studied theoretically using a generalized gradient approximation along with Hubbard potential (GGA + U) in the domain of density functional theory (DFT). A decrease in the lattice constants of these compounds is observed when going from CaMn3V4O12 to CaCu3V4O12 due to the increase in the number of electrons in the trending of the metals. Electron charge densities in different crystallographic planes show that the bonds between Ca–O, A/V–O and A–V are ionic, covalent and metallic, respectively. The electronic band structures show the metallic behavior of these compounds except that CaMn3V4O12 and CaFe3V4O12 are half-metals. The elastic moduli of these compounds indicate the hardness and increases in a sequence going from CaMn3V4O12 to CaCu3V4O12, and also reveal their ductile nature. The optimized energies in different magnetic phases and the post-DFT calculations confirm that CaMn3V4O12 and CaCo3V4O12 are anti-ferromagnetic, and CaFe3V4O12 and CaNi3V4O12 are ferromagnetic, whereas CaCu3V4O12 is a paramagnetic material. Based on the above properties, it is expected that these compounds are potential candidates for storage devices.