RAMAN-STUDY OF CRYSTAL-FIELD EXCITATIONS IN ND1.85CE0.15CUO4

Eighteen Raman active crystal-field (CF) excitations were detected in Nd1.85Ce0.15CuO4. They correspond to transitions within the I-4(9/2), I-4(11/2), and I-4(13/2) multiplets associated with the inequivalent s ites of the Nd3+ ion. Three sets of CF parameters which describe the o bserved energy spectra were derived. One of the three Nd3+ sets descri bes levels which are very similar to those observed in Nd2CuO4 while t he two others correspond to sites affected by the cerium doping. Krame rs doublet splitting is also present indicating that antiferromagnetis m persists in the CuO2 planes even with 7.5% cerium doping.