Abstract
To investigate interrelations among thermodynamic properties, crystal structures and electronic states in Fe1−yNiyTiHx (where 0<x<1.20; y=0.20, 0.35 and 0.50), pressure-composition isotherms (PCT curves), X-ray diffractographs and Mössbauer spectra of these hydrided compounds have been measured. Clear correlations are found between the formation enthalpies, lattice parameters and isomer shifts of β hydrides of the above compounds and Ni or H concentration. The thermal stability of these hydrides which increases with the Ni concentration is related to the chemical interaction between Fe and H atoms that is enhanced by Ni atoms in the hydrides.
