Radio-Frequency Orientation ofSb122

Radioactive ${\mathrm{Sb}}^{122}$ donors in a doped silicon crystal have been oriented by saturation of forbidden transitions and by the Overhauser method. Double-resonance experiments in which an electron and a nuclear transition were saturated simultaneously were used to determine the ${\mathrm{Sb}}^{122}$ hyperfine splitting. A short discussion is given of how the nuclear relaxation mechanisms affect the double-resonance orientation signals. The hyperfine splitting of ${\mathrm{Sb}}^{122}$ has been found to be -132.59±0.10 Mc/sec and its spin 2. The gyromagnetic ratio is -0.952±0.010.