Thermal Expansion of Some Cubic Refractory Compounds of Thorium

The thermal expansion of a number of cubic refractory compounds of thorium was measured by high-temperature X-ray diffraction. The coefficients of thermal expansion range from 7.5 to 8.2 × 10⁻⁶/°C for ThN, ThC_0.84, ThP_0.71, ThP_0.61, and Th₃P₄ between 900° and 1300°, 1450°, 1750°, 1750°, and 1150°, respectively; the coefficients for ThS, ThB₆, and ThO₂ are in the range of 11.2 to 12.0 × 10⁻⁶/°C between 900° and 1400°, 1700°, and 2100°, respectively. The results are discussed in relation to other properties of these compounds.