High-Pressure Mössbauer Studies of Magnetism in ScFe_2 and Sc_{0.4}Ti_{0.6}Fe_2 Laves Phases

• Authors: K. Rupprecht , J. Lu , G. Wortmann , J. Przewoźnik , J. Żukrowski
• Languages of publication: EN

Abstracts

EN

We report on ^{57}Fe-Mössbauer studies of the magnetic properties in ScFe_2 and Sc_{0.4}Ti_{0.6}Fe_2 performed as a function of pressure and temperature. Both systems crystallize in the C14-type Laves phase structure with two different Fe sites 6h and 2a. The ferromagnetic properties of ScFe_2 (T_C=540 K at ambient pressure) change around 30 GPa to antiferromagnetic order of the 6h sites with non-magnetic 2a sites. The ordering temperature is lowered to T_N=300 K at 51 GPa. This pressure-dependent behaviour of ScFe_2 resembles that observed within the Sc_{1-x}Ti_xFe_2 series as a function of x. In ferromagnetic Sc_{0.4}Ti_{0.6}Fe_2 we observe, as a function of temperature and of pressure, an abrupt high-moment to low-moment transition of the Fe band moments of the 6h sites, accompanied by a rearrangement of the spin directions. In both systems the decrease in the Fe moments is accompanied by a strong increase in the volume coefficient of the isomer shift, originating from a reduced s-electron shielding capability of the d-electrons in the low-moment state.

Keywords

EN

75.50.Bb   76.80.+y  

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2001
• Volume: 100
• Issue: 5
• Pages: 789-797

Dates

published

2001-11

received

2001-05-14

References

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Identifiers

DOI

10.12693/APhysPolA.100.789