The Variation of the Elastic Constants of Crystalline Sodium with Temperature Between 80°K and 210°K

Methods are described for growing single crystals of sodium in the form of rods 4. 7 mm in diameter and 10 cm long, for handling the crystals in an atmosphere of helium, and for measuring the principal elastic moduli at low temperatures. Values of the adiabatic and isothermal moduli and constants are tabulated at ten degree intervals between 80^ and 210^. The value of the Debye characteristic temperature, calculated from the values of the elastic constants at 80^, is 164^.