The structure, electronic, and magnetic properties of PbRuO3 under hydrostatic pressure: A first-principles study

Abstract

Density functional theory in the local spin density approximation is used to investigate the structural, electronic, and magnetic properties of PbRuO3 under hydrostatic pressure. The calculated results show that under hydrostatic pressure, the ground state of Pm[Formula: see text]m PbRuO3 is a ferromagnetic metal. The covalent bond of Pb–O strengthens as hydrostatic pressure increases, the exchange splitting of up- and down-spin channels of Ru 4d t2g weakens, and the magnetic properties decrease. The calculated ground state of Pbnm PbRuO3 is a paramagnetic metal, which is consistent with the experimental results at P = 0 GPa. The ground state of Imma PbRuO3 has weak ferromagnetism, which is close to the experimental results at P = 0 GPa. The Pbnm–Imma phase transition occurs when passing the critical hydrostatic pressure. The main reason is the distortion of Pb2+ at the A-site, which changed the bond length of Pb–O and the covalent strength of Pb–O, affecting the electron occupation of Ru 4d and leading to the Pbnm–Imma phase transition.