5F BAND METAMAGNETISM IN UCOAL - EFFECTS OF ALLOYING AND PRESSURE

We report on the results of magnetisation and susceptibility studies o f the effects induced in the 5f band metamagnet UCoAl by doping with o ther elements and/or by application of external pressure. In majority of aspects UCoAl shows strong similarities to the 3d band metamagnets CoS2, YCo2 and LuCo2, which suggests an essentially same origin of fie ld-induced phenomena in both the classes of materials. The main role o f the observed alloying and pressure effects can be attributed to the involvement of the 5f-ligand hybridisation in both the U Sf-moment for mation and the 5f-5f exchange interactions.