Thermodynamic Properties of Holmium Monogermanide

Abstract

The heat capacity and enthalpy of HoGe is investigated for the first time over a temperature range between 51.62 and 2096 K. The values of heat capacity, entropy, reduced Gibbs energy (J ∙ mole^–1 ∙ K^–1), and enthalpy (J ∙ mole^–1) are determined at 298.15 K: C_P°(Т)= = 49.63 ± 0.20; Sо(Т) = 89.1 ± 0.7; Ф’(Т) = 50.9 ± 0.8; Но(Т) – Но(0 К) = 11391 ± 57. Temperature dependences of enthalpy (J∙mole^–1) for holmium monogermanide are determined as follows: Но(Т) – Но(298.15 К) = 8.474•10^–3 • Т² + 47.13 • Т + 226747 • Т^–1 – 15565 and Но(Т) – Но(298.15 К) = 88.91 ∙ Т – 26507, for 298.15–1765 К and 1951–2096 К, respectively. The enthalpy and entropy of HoGe melting are calculated: Т_m = 1765 ± 35 К, ΔН_m = 36.3 ± 2.9 кJ ∙ mole^–1, ΔS_m = 20.5 ± 1.6 J ∙ mole^–1 ∙ К^–1.