"par exemple des composés intermétalliques cubiques, type phase de Laves [Il entre les terres rares et le cobalt. Le moment du cobalt est voisin de 1 ..."
http://hal.archives-ouvertes.fr/docs/00/21/40/55/PDF/ajp-jph...

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Note added at 10 mins (2009-04-17 14:06:30 GMT)
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"Laves phases are intermetallic phases that have composition AB2 and are named for Fritz Laves who first described them. The phases are classified on the basis of geometry alone. There are three different classification classes: cubic, hexagonal MgZn2, and hexagonal MgNi2. The latter two classes are unique forms of the hexagonal arrangement, but share the same basic structure. In general, the A atoms are ordered as in diamond, hexagonal diamond, or a related structure, and the B atoms form tetrahedra around the A atoms for the AB2 structure.[1] Laves phases are of particular interest in modern metallurgy research because of their abnormal physical and chemical properties. Many hypothetical or primitive applications have been developed. However, little practical knowledge has been elucidated from Laves phase study so far."
http://en.wikipedia.org/wiki/Laves_phase