Abstract
The susceptibility of ytterbium metal has been measured at room temperature and between 1 3°K and 80°K. Its magnitude seems to indicate that the atoms are mostly in the 1S state with the 4f shell completely filled, only about 1 atom in 260 being in the 2F7/2 state with 13 electrons in the 4f shell. The paramagnetic saturation effect at the lowest temperatures seems to confirm this. The material has been tested for superconductivity down to 1.24°K in fields as low as 10 oersteds, with a negative result.