Hydrogenation inducing ferromagnetism in the ternary antiferromagnet NdCoSi.
The hydride NdCoSiH obtained by exposure at 523 K of the ternary antiferromagnet NdCoSi under a pressure of 4 MPa of hydrogen crystallizes in the tetragonal ZrCuSiAs-type structure where H atoms occupy the tetrahedral [Nd(4)] site. The hydrogenation induces an increase in the unit cell volume close to 6%. The investigation of NdCoSiH by magnetization measurements reveals its ferromagnetic behavior below T(C) = 20.5(5) K. Neutron powder diffraction shows that the T(C) temperature is associated with a ferromagnetic arrangement of the Nd moments (2.3(2) mu(B) at 1.5 K) parallel to the c axis as observed for NdFeSi. The magnetic properties, magnetic structure, and the value of the Nd ordered magnetic moment evidenced for NdCoSiH are discussed using both band structure calculations and a comparison with the behavior of NdCoSi and NdFeSi.
Tencé
Sophie
S
CNRS, Université de Bordeaux, ICMCB, 87 avenue du Docteur Albert Schweitzer, 33608 Pessac Cedex, France.
Matar
Samir F
SF
André
Gilles
G
Gaudin
Etienne
E
Chevalier
Bernard
B