Calorimetric study of Zn13La

Abstract

Abstract The thermodynamic properties of Zn13La were investigated by calorimetry. The standard entropy of formation at 298 K, Δ f S 298 ° ${{\Delta }_{\text{f}}}S_{298}^{{}^\circ }$ was determined from measuring the heat capacities, Cp , from near absolute zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, Δ f H 298 ° ${{\Delta }_{\text{f}}}H_{298}^{{}^\circ }$ was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, Δ f G 298 ° ${{\Delta }_{\text{f}}}G_{298}^{{}^\circ }$ was determined from these data. The coefficient, γ, of the electronic term contributing to the heat capacity of Zn13La was similar to the composition average of the values of pure Zn and La, indicating that the 5d- and 4f-electron states for La are localized in the vicinity of the Fermi energy level.