MAGNETIC HYPERFINE FIELDS IN THE HEUSLER ALLOYS CO2YZ (Y=SC, TI, HF, V, NB, Z = AL, GA, SI, GE, SN)

The magnetic hyperfine field acting on Ta at the non-magnetic transiti on element site has been investigated in the Heusler alloys Co2(SC, Hf , V)Sn, Co2ScGa, Co2(V, Nb)Al and Co2Ti(Si, Ge) by TDPAC measurements utilizing the 133-482 keV gamma-gamma cascade in Ta-181 following the beta- decay of Hf-181. An important conclusion is that the reduced mhf either on the non-magnetic transition element site or on the s-p elem ent site depends mainly on the chemical nature of the non-magnetic tra nsition element rather than any other factor, e.g. the local moment mu (Co) of the alloy.