A localized magnetic moments

Fig. 5.28 The 4/ shell of each Gd atom carries a local magnetic moment which remains constant with temperature. The relative axes of these magnetic moments fluctuate with rising temperature. This behavior can be modeled by spin waves being characterized by the angle a between nearest neighbors. From [127], copyright 1998, reproduced with permission from World Scientific Publishing Co. Pte. Ltd...

For Ti, V and Zr carbides and Sc and Ti nitrides, such destabilising impurities are Cr, Mn and Fe (and V for ZrC). Spin polarisation of the states by the impurity atoms results in energy splitting of spin-up and spin-down states and so, in a sharp drop in the Af ( p) value accompanied by the formation of a local magnetic moment at the impurity... 

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