Hydrogenation of the intermediate valence ternary stannides CeRhSn and CeIrSn
Langue
en
Article de revue
Ce document a été publié dans
Solid State Sciences. 2006, vol. 8, n° 8, p. 1000-1008
Elsevier
Résumé en anglais
CeRhSn and CeIrSn were synthesized from the elements via arc-melting. A single crystal from the CeIrSn sample was investigated on the basis of X-ray diffractometer data: ZrNiAl type, P2m, a=743.8(2), c=407.58(7) pm, ...Lire la suite >
CeRhSn and CeIrSn were synthesized from the elements via arc-melting. A single crystal from the CeIrSn sample was investigated on the basis of X-ray diffractometer data: ZrNiAl type, P2m, a=743.8(2), c=407.58(7) pm, wR2=0.0308, 352 F2 values and 14 variable parameters. An important structural feature of CeIrSn are relatively short Cesingle bondIr distances (4×303 and 1×308 pm). Hydrogenation of these ternary stannides leads to the formation of the new hydrides CeRhSnH0.8 and CeIrSnH0.7 which adopt the same crystal symmetry as the original compounds but a larger unit cell volume after hydrogen insertion. Magnetization, electrical resistivity and thermoelectric power measurements reveal a change of the ground state of the cerium from intermediate valence to the nearly trivalent state induced by hydrogenation. Moreover, 119Sn Mössbauer spectroscopic data of CeRhSn, CeIrSn and their hydrides at 4.2 and 78 K indicate only one tin site. The isomer shifts are slightly larger for the hydrogenated samples suggesting a slightly higher s electron density at the tin nuclei of the hydrides.< Réduire
Mots clés en anglais
Cerium
Hydrogenation
Crystal structure
Magnetism
Origine
Importé de halUnités de recherche