Title :
The role of a critical distance in RMn2 compounds
Author :
Kim-Ngan, N.H. ; Brommer, P.E. ; Franse, J.J.M.
Author_Institution :
Van der Waals Lab., Amsterdam Univ., Netherlands
fDate :
3/1/1994 12:00:00 AM
Abstract :
In the RMn2 system, the antiferromagnetically ordered Mn moments are reported to disappear at a reduction of the Mn-Mn distance, either by applying external pressure or by alloying. We illustrate the phenomena for the hexagonal NdMn2 compound. The Neel temperature in the (Nd,Lu)Mn2 system is found to vanish; at substitution of 30% of Nd by Lu, considered to be equivalent-to applying a pressure of 24.5 kbar. Antiferromagnetic order of the Mn sublattice, however, vanishes already at substitution of 7% of Mn by Cu and of 3% of Mn by Fe in the NdMn2, being equivalent to an external pressure of only 4 kbar. High-pressure studies on the Nd(Mn,Cu)2 system show that the effect of an external pressure on the Neel temperature decreases markedly with increasing Cu concentration, in contrast to what is expected in a critical distance model
Keywords :
Neel temperature; antiferromagnetic properties of substances; manganese alloys; rare earth alloys; Mn-Mn distance; NdMn2; Neel temperature; antiferromagnetically ordered Mn moments; critical distance; external pressure; hexagonal NdMn2; Chemical compounds; Conductivity measurement; Extrapolation; Iron; Lattices; Performance evaluation; Temperature dependence; Testing; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
