Nd2Ni2MgH8 hydride: Synthesis, structure and magnetic properties

Silvie Maskova , Jean-Noel Chotard (1, 2, 3) , Roman V. Denys , Khrystyna Miliyanchuk , Volodymyr Yartys (4) , Mauro Giovannini , Lev Akselrud (5) , Itzhak Halevy , Jan Prokleska , Ladislav Havela

1 LRCS - Laboratoire réactivité et chimie des solides - UMR CNRS 7314
2 RS2E - Réseau sur le stockage électrochimique de l'énergie
3 ALISTORE-ERI - Advanced Lithium Energy Storage Systems - ALISTORE-ERI
4 INSTITUTE FOR ENERGY TECHNOLOGY, PO BOX 40, 2007, KJELLER, NORWAY - Institute for Energy Technology, PO Box 40, 2007, Kjeller, Norway
5 CPfS - Max-Planck-Institut für Chemische Physik fester Stoffe

Hydrogen interaction with intermetallic compound Nd2Ni2Mg crystallizing in the tetragonal Mo2FeB2 type of structure leads to the formation of hydride/deuteride containing 7.4-8 H(D)/f.u. Hydrogen absorption is accompanied by a monoclinic deformation of the unit cell with the crystal structure data refined from Synchrotron XRD (Sp. gr. P2(1)/c; a = 11.60733(5) angstrom; b = 7.66057(3) angstrom; c = 11.78743(5) angstrom, beta = 92.4126(4)degrees, V = 1047.194(8) angstrom(3)) and high resolution powder XRD data. The formed interstitial hydride disproportionates during heating forming NdH2. Nd2Ni2Mg is an antiferromagnet with the Neel temperature T-N approximate to 19 K. Presence of another magnetic phase transition at 14 K together with two metamagnetic transitions indicates a complicated magnetic phase diagram. The hydrogenation reduces T-N to 1.0 K. (C) 2017 Elsevier Ltd. All rights reserved.

Domaines: Matériaux

Silvie Maskova, Jean-Noel Chotard, Roman V. Denys, Khrystyna Miliyanchuk, Volodymyr Yartys, et al.. Nd2Ni2MgH8 hydride: Synthesis, structure and magnetic properties. Intermetallics, 2017, 87, pp.13-20. ⟨10.1016/j.intermet.2017.03.023⟩. ⟨hal-03611611⟩