New quaternary hydride CeZnSnH_1.5 : structure, Magnetism, and chemical bonding

Wilfried Hermes (1) , Bernard Chevalier (2) , Ute Ch. Rodewald (1) , Samir F. Matar (2) , François Weill (2) , Inga Schellenberg (3) , Rainer Pöttgen (1) , Heiko Lueken (4) , Manfred Speldrich (4)

1 Institut für Anorganische und Analytische Chemie
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
3 Institut für Anorganische und Analytische Chemie
4 IAC RWTH - Institute of Inorganic Chemistry [Aachen]

The quaternary hydride CeZnSnH_1.5 was synthesized from a CeZnSn precursor upon hydrogenation at 553 K and 4 MPa H₂ pressure. Single-crystal X-ray diffraction data reveal that the metal atoms adopt an YPtAs-type structure: P6₃/mmc, a = 449.34(9) and c = 1731.3(4) pm, wR2 = 0.0493, 218 F² values, and 12 variables. The hydrogen atoms fill three crystallographically independent ZnCe₃ tetrahedral sites, leading to the composition CeZnSnH_1.5. Hydrogenation anisotropically modifies the unit cell parameters, i.e., 456.7 → 449.34 pm (−1.6%) for a and 1673.8 → 1731.3 pm (+3.4%) for c. This leads to a drastic flattening of the two-dimensional [ZnSn] layers and a decrease of the Zn−Sn distances from 271 to 260 pm. Hydrogenation increases the Curie temperature from 4.8 K for CeZnSn to 7.3 K for CeZnSnH_1.5.

Mots clés: Hydride; Crystal chemistry; CeZnSnH1.5; Magnetic properties; Electronic structure

Domaines: Matériaux

Wilfried Hermes, Bernard Chevalier, Ute Ch. Rodewald, Samir F. Matar, François Weill, et al.. New quaternary hydride CeZnSnH_1.5 : structure, Magnetism, and chemical bonding. Chemistry of Materials, 2011, 23 (5), pp.1096-1104. ⟨10.1021/cm1016504⟩. ⟨hal-00575849⟩