CRYSTAL-FIELD EXCITATIONS IN RE2CUO4 (RE-EQUIVALENT-TO-PR, ND)

The magnetic excitation spectra of Pr2CuO4 and Nd2CuO4 determined by inelastic neutron scattering over the temperature range 15-300 K are reported. Well-defined transitions between the rare earth ion crystal field levels have been observed up to about 100 meV for both compounds. The results are analyzed in terms of a crystal field model under the scheme of intermediate coupling calculated by spherical tensor techniques. The calculated crystal field excitation spectra and magnetic susceptibilities agree well with experiments. No measurable influence of the rare earth crystal field structures by the antiferromagnetic ordering of copper spins is found in these materials.