Change in Pr-4f Ground State in Pr1−xYxCoO3

Abstract

We have investigated the magnetic properties of Pr1−xYxCoO3. By the introduction of Y at the Pr site, the magnetism of Pr-4f electrons changes from temperature-dependent Van Vleck paramagnetism with a nonmagnetic 4f2 ground state to Curie–Weiss paramagnetism with a magnetic 4f1 ground state. As the origin of the change in the magnetic property, the increment of the ligand hole transfer from Co(3d)–O(2p) molecular orbitals into Pr-4f2 states by the introduction of Y ions at the Pr sites is discussed, which results from the hybridization between Pr-4f and Co-3d orbitals via O-2p orbitals.