ИСТИНА

It is known, that samples of the RNi3 (R- Ce, Ho)-based hydride structure with medium concentration (3-4 H/IMC) have different anisotropy of the crystal lattice. In structure of these hydrides, hydrogen atoms are ordered and have long-rang interaction each with other. In contrary, in the structure of hydride phases with low hydrogen amount with small anisotropy of the lattice, hydrogen atoms are as a disordered interstitial solution, without any interaction. Decreasing of the temperature leads to the hydrogen atoms redistribution in the hydrogen sublattices in hydride samples with low concentration. This process may leads to possibility of appearing of the long-range interaction between atoms of hydrogen. For better understanding this behavior of hydrogen in the crystal lattice, it is necessary to perform the study of their structure. At present work using neutron diffraction method were study samples of the RNi3 (R- Ce, Ho)-based hydrides containing about of 1.0 Н/IMC at 5K and 293K temperature. For this study, samples with deuterium were prepared. Obtained neutron data allows to determinate site positions of the hydrogen atoms and monitoring hydrogen redistribution in the sites of the structure.