Thermodynamic studies on ThGa2

The enthalpy of formation of ThGa2 was determined by high temperature gallium solution calorimetry and precipitation calorimetry. The values thus obtained are −(55.1±4.8) and −(69.6±5.6) kJ g atom−1 with reference to α-thorium and solid gallium at 298.15 and 1100 K, respectively. These are the first calorimetric results for the enthalpy of formation of ThGa2. The Gibbs energy of formation of ThGa2 with reference to α-thorium and liquid gallium was determined by molten salt galvanic cell measurements to be −75.1+0.024T kJ g atom−1 in the temperature range 682–891 K. The partial molar excess Gibbs energy of thorium in liquid gallium in the saturated solution at 787 K was determined to be −(123.3±4.7) kJ g atom−1. The partial molar enthalpy of solution of thorium in liquid gallium at infinite dilution at 1095 K was determined to be −(178.6±6.8) kJ g atom−1 and partial molar enthalpy of thorium in liquid gallium in the saturated solution at 787 K to be −(164.2±4.7) kJ g atom−1.