Abstract
Crystal structure and magnetic properties of CeNiH3.7 were studied by the means of the powder X-ray diffraction, specific heat, and dc and ac magnetization techniques. It was established that hydrogenation stabilizes the Ce valence and turns CeNi-H into a dilute Kondo system with TK = 3.7 K.
The Kondo screening in CeNiH3.7 is suppressed by the applied magnetic field, although it still affects the properties of CeNiH3.7 at 14 T, as indicated by the enhanced g-coefficient of electronic specific heat, which remains more than 2 times larger compared to the precursor compound CeNi. Its zero-field value is as high as 1890 mJ/(mol K2).
Hydrogenation acts primarily as the negative pressure agent in CeNiH3.7, while the role of H-metal bonding is secondary.