Effect of electron correlations on the electronic structure and magnetic properties of the perovskite-like high-pressure phase ErCu$_3$V$_4$O$_{12}$

The electronic structure and magnetic properties of double perovskite ErCu$_3$V$_4$O$_{12}$ have been investigated in the framework of the projector augmented-wave method. It has been shown that the electron correlations play an important role: the calculations in the one-electron approximation predict that the ground state of ErCu$_3$V$_4$O$_{12}$ is a magnetic metallic state, while with the inclusion of electron-electron correlations, it is a ferrimagnetic semimetallic state. It has been found that the magnetic Cu–Cu and V–V couplings are ferromagnetic and that the Cu–V magnetic coupling is antiferromagnetic.