The local magnetism at R and In sites in RNiIn (R=Gd, Tb, Dy, Ho) compounds was investigated by measuring hyperfine interactions via perturbed gamma-gamma angular correlation (PAC) technique using La140–Ce140 and In111–Cd111 probe nuclei. PAC measurements carried out below respective TC for each compound showed a combined electric quadrupole plus magnetic dipole interaction for Cd111 probe at In sites and a pure magnetic interaction for Ce140 at R sites. The temperature dependence of the magnetic hyperfine field (Bhf) shows that, whereas the Bhf values at rare-earth sites measured with Ce140 drop to zero at temperatures around the expected TC for each compound, the respective fields at In sites measured with Cd111 drop to zero at lower temperatures. The difference between the temperatures at which Bhf is zero for Ce140 and Cd111 probes when compared with TC of each compound shows that this difference decreases with decreasing TC values. The results are discussed in terms of the Ruderman-Kittel-Kasuya-Yosida model for magnetic interactions and the crystalline electric field.

The local magnetic interaction at the transition metal sites in RMO 3 (R = La, Nd; M = Cr, Fe) compounds has been investigated by perturbed angular correlation (PAC) technique using 181 Hf→ 181 Ta probe nuclei. The present measurements cover a temperature range from 10 K to 1000 K. Above the respective Néel temperature, each compound shows a unique quadrupolar frequency that decreases linearly with temperature. These interactions were assigned to the radioactive probe substituting Cr or Fe sites. Below T N , a combined electric plus magnetic hyperfine interaction was observed. The magnetic interaction revealed that the super transferred hyperfine fields on 181 Ta at the Cr sites in (La,Nd)CrO 3 extrapolated to 0 K, are much smaller than the corresponding values at Fe sites in (La,Nd)FeO 3 . This difference was attributed to different distribution of d electrons in Cr 3+ (3d 3 ) and Fe 3+ (3d 5 ) ions in each compound. As the fields for Nd compounds are smaller than those for La compounds, the role of rare-earth ions in the magnetism of these oxides is also discussed.

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