Spin and Magnetic Moment ofEu152andEu154by Paramagnetic Resonance

Abstract

The microwave paramagnetic resonance hyperfine structures of 13-year ${\mathrm{Eu}}^{152}$ and 15-year ${\mathrm{Eu}}^{154}$ have been observed in a sample of ${\mathrm{Eu}}^{2+}$ which was incorporated in a KCl powder. From the number of his lines the spins were found to be $I({\mathrm{Eu}}^{152})=3$ and $I({\mathrm{Eu}}^{154})=3$. Neglecting hfs anomalies, from the ratios of the total hfs splitting these magnetic moment ratios were obtained: $\frac{|\ensuremath{\mu}({\mathrm{Eu}}^{154})|}{|\ensuremath{\mu}({\mathrm{Eu}}^{153})|}=1.308\ifmmode\pm\else\textpm\fi{}0.004$, $\frac{|\ensuremath{\mu}({\mathrm{Eu}}^{152})|}{|\ensuremath{\mu}({\mathrm{Eu}}^{151})|}=0.5574\ifmmode\pm\else\textpm\fi{}0.006$, $\frac{|\ensuremath{\mu}({\mathrm{Eu}}^{151})|}{|\ensuremath{\mu}({\mathrm{Eu}}^{153})|}=2.264\ifmmode\pm\else\textpm\fi{}0.006$. Using $\ensuremath{\mu}({\mathrm{Eu}}^{153})\ensuremath{\cong}1.6$ nm, we find $|\ensuremath{\mu}({\mathrm{Eu}}^{154})|\ensuremath{\cong}2.1$ nm and $|\ensuremath{\mu}({\mathrm{Eu}}^{152})|\ensuremath{\cong}2.0$ nm. These results are discussed in relation to the nuclear shell model.