Abstract
The bonding nature of hydrogenated palladium, nickel and FCC iron-nickel alloys was investigated by means of differential scanning calorimetry (DSC). A progressive endothermic or exothermic reaction process was observed as the temperature was raised. From the DSC measurements and their analysis, the differential heats of reaction for Pd-H, Ni-H, and Fe-33 at.% Ni-H alloys were obtained and interpreted semi-quantitatively in terms of the energy of elastic dipole interactions and electronic metal-hydrogen interactions. The nature of bonding between metal and hydrogen atoms was discussed accordingly.