Structural and magnetic properties of the new hydride CeAuAlH1.4(1)

Bernard Chevalier (1) , Jean-Louis Bobet (1) , Myrtil L. Kahn (1) , François Weill (1) , Jean Etourneau (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

CeAuAl which orders antiferromagnetically below TN=3.8 K is considered as a Kondo lattice. This intermetallic absorbs hydrogen at room temperature and at a pressure of 4.5 MPa. The newhydride CeAuAlH1.4(1) is stable in air and crystallises in a derivative structure of the hexagonal Ni2In-type with a=0.4427(1) nm and c=0.8467(1) nm as unit cell parameters. Moreover, it exhibits an antiferromagnetic order below TN=8.0(2) K and another magnetic transition at T1=3.0(2) K. The strong increase of the TN-temperature after the insertion of hydrogen in CeAuAl can be explained on the basis of the Doniach diagram; the increase of the unit cell volume induced by this insertion leads to a strong reduction of the influence of the Kondo effect.

Mots clés: Rare earth compounds; Hydrogen absorbing materials; X-ray diffraction; Magnetic measurements

Domaines: Matériaux

Bernard Chevalier, Jean-Louis Bobet, Myrtil L. Kahn, François Weill, Jean Etourneau. Structural and magnetic properties of the new hydride CeAuAlH1.4(1). Journal of Alloys and Compounds, 2002, 334 (1-2), pp.20-26. ⟨10.1016/S0925-8388(01)01748-0⟩. ⟨hal-00708239⟩