Calorimetric investigation of the interaction in the LaNi2.5Co2.4Mn0.1-H-2system

The interaction of hydrogen with LaNi2.5Co2.4Mn0.1 was studied in a wide te mperature range (308-393 K) using the technique of "calorimetric titration. " The shape of the p-C-T diagrams changes with temperature change. The valu es of enthalpy and entropy of hydrogenation of LaNi2.5Co2.4Mn0.1 were obtai ned for the first time by direct calorimetric investigations and p-C-T meas urements. The volume effects of the hydrogen absorption reaction are consid ered, and the LaNi2.5Co2.4Mn0.1H4.9 hydride is shown to retain the CaCu5-ty pe hexagonal structure.