Suppression of the Nuclear Heat Capacity in Bismuth Metal by Very Slow Spin-Lattice Relaxation, and a New Value for the Electronic Specific Heat

The specific heat of metallic bismuth has been measured from 0.05 to 0.8 K. The nuclear-quadrupole heat capacity expected from NMR measurements is not observed, allowing a more accurate determination of the electronic specific heat than has been possible previously. A lower limit for the nuclear spin-lattice relaxation time is estimated.