Spin-state transitions in PrCoO3investigated by neutron scattering

Abstract

Pulsed neutron diffraction and inelastic neutron scattering were performed on the orthorhombic perovskite PrCoO${}_{3}$ to investigate possible spin-state transitions arising from Co${}^{3+}$ ions. Although the crystal symmetry is orthorhombic, no evidence for a Jahn-Teller distortion is observed in either the average or local crystal structures, suggesting that the intermediate-spin Co${}^{3+}$ state, if present, does not give rise to a static Jahn-Teller distortion. While previous measurements suggested that spin excitations may occur at about 200 K, we find from the inelastic neutron measurements that the crystal-field excitations from Pr${}^{3+}$ dominate the inelastic spectrum, and no magnetic excitation linked to Co${}^{3+}$ can be clearly discerned up to room temperature.