Thermodynamics of Formation of HoGe_3-x and HoGe_2-y Higher Holmium Germanides

L.Goncharuk,

† V.Sidorko,

I.M.Obushenko

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Omeliana Pritsaka str.,3, Kyiv, 03142, Ukraine
Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2012, #05/06
http://www.materials.kiev.ua/article/1040

Abstract

The Gibbs energy, enthalpy, and entropy of formation of HoGe_3-x (HoGe_2,7) and HoGe_2-y (HoGe_1,8) from solid compounds are determined by e.m.f. measurement in the temperature range 770–965 K. The formation enthalpy of the highest holmium germanide is in good agreement with Δ_fH⁰ (HoGe_2,7) calculated from the limiting mixing enthalpy of Ho in liquid germanium on the assumption that for solid alloys in the [HoGe_2,7 + Ge] region remains the same as for liquid alloys.