Electric Quadrupole Effects in Nuclear Magnetic Resonance in the Case of Large Nuclear Spin. The Nuclear-Magnetic-Resonance Spectrum of Solid Indium

The nuclear-magnetic-resonance spectrum of ${\mathrm{In}}^{115}$ in polycrystalline indium (powder) reveals a number of unusual features stemming from the combination of large quadrupole interaction and large nuclear spin ($I=\frac{9}{2}$). The crossing of several Zeeman transitions, the occurrence of non-90° satellite lines, and the occurrence of forbidden transitions ($\Delta m=\pm 2$) have been verified experimentally, and the experimental results have been compared with a detailed theoretical calculation of the spectrum based on exact numerical diagonalization of the secular determinant. At room temperature, the isotropic and anisotropic Knight-shift tensor components have the values $K_{\mathrm{iso}}=+(0.82\mathrm{}\pm 0.04)\%$ and $K_{\mathrm{ax}}=-(0.14\mathrm{}\pm 0.04)\%$.