High-pressure Moessbauer study of hyperfine interactions in europium intermetallic compounds

The authors report a systematic 151Eu Moessbauer study of hyperfine interactions as a function of applied pressure for several intermetallic compounds. In all cases the isomer shift S, and the magnetic hyperfine field, Hsub(hf), varied approximately linearly with the applied pressure while an increase of S with pressure was observed for all the compounds studied, both positive and negative pressure coefficients of Hsub(nf) were found. While the magnetic hyperfine splitting decreases with pressure in EuZn2, and Eu metal, it increases in EuCu2, EuCu5, EuAl2, EuAl4 and EuSn3