Multinary Intermetallics from Molten Al. Synthesis of SmNiAl 4 Ge 2 and YNiAl 4 Ge 2 . Possible Spin Frustration in Separated Triangular Sm 3+ Layers
1999; American Chemical Society; Volume: 11; Issue: 9 Linguagem: Inglês
10.1021/cm990155+
ISSN1520-5002
AutoresB. Sieve, X. Chen, J. A. Cowen, P. Larson, S. D. Mahanti, Mercouri G. Kanatzidis,
Tópico(s)Iron-based superconductors research
ResumoSmNiAl4Ge2 crystallizes from molten Al containing Sm, Ni, and Ge. The compound crystallizes in the rhomohedral space group R3m with a = 4.1121(6) Å, c = 31.109(6) Å, and V = 455.5(1) Å3. The YNiAl4Ge2 analogue is also stable. The crystal structure consists of layers of [NiAl4Ge2]3- separated by monolayers of hexagonally close-packed Sm3+ ions. The Ni atoms are surrounded by eight Al atoms in the structure. Each Sm atom has an octahedral environment of six Ge atoms. The magnetism of SmNiAl4Ge2 is unusual, possibly reflecting the presence of geometrical spin frustration. The magnetization exhibits a well-defined hysteresis loop, without signs of ferromagnetism. It also exhibits irreversibility in the field-cooled and zero-field-cooled magnetization but without the typical characteristic spin glass behavior.
Referência(s)