Nuclear Magnetic Resonance and Mössbauer Effect Study of Sn119 in Rare Earth‐Tin Intermetallic Compounds

The nuclear magnetic resonance and Mössbauer effect of Sn119 have been studied in the cubic intermetallic compounds RSn3 (R = La, Ce, Pr, Nd, Sm, and Yb). Both the isotropic and anisotropic components of the Knight shift were determined in the temperature range 77 to 400°K. In the cases of PrSn3 and NdSn3 in which the shift measurements are proportional to the magnetic susceptibility, the results may be understood in terms of the Ruderman‐Kittel‐Kasuya‐Yosida theory, with an exchange interaction, T = −0.2 eV. The cases of CeSn3 and SmSn3 do not appear to be interpretable in terms of the RKKY theory. For PrSn3, NdSn3, and SmSn3 the Mössbauer effect of the Sn119 yielded a resolved quadrupole splitting of approximately 1.1 mm/s, independent of temperature in the range 4.2 to 300°K. The isomer shift was +0.70 mm/s, relative to Mg2Sn, also independent of temperature. The measured quadrupole coupling has been compared with that expected on the basis of the ionic model. No magnetic splitting was ever unambiguously observed, even at 1.5°K. Assuming that the magnetic splitting remains masked by the quadrupole interaction leads to an estimate of Heff ≦ 9 × 103 Oe in PrSn3 and NdSn3.