Optically induced dynamic nuclear polarization in CdS (resistivity 1.8x10(1
0) Omega cm, dark) is observed by radio-frequency detection of the Cd-113 n
uclear magnetic resonance signal. At 2 K, the nuclear-spin transitions are
emissive when compared to the thermal polarization, and no dependence on th
e helicity of the pumping light is observed. [S0163-1829(99)14103-1].