SPECIFIC-HEAT OF THE HF2FE, HF2CO, AND HF2RH INTERMETALLIC COMPOUNDS

The specific heat under constant pressure, C-p, of intermetallic compo unds Hf2Fe, Hf2Co and Hf2Rh with the Ti2Ni structure was obtained by m eans of differential thermal analysis in the temperature range 275-740 K. The results differ significantly from the Debye theory, even when a correction for optical phonons in Einstein approximation is consider ed, which indicates existence of a defect contribution to the specific heat. Relative entropy has been determined and the obtained results w ere fitted and analysed. The anomalous temperature behaviour of C, is discussed, having in mind results of previous investigations of these and similar systems, obtained by other methods.