LOCAL SPIN CONFIGURATIONS OF Fe ATOMS IN MICROINHOMOGENEOUS PdMn_xFe_(1-x) ALLOYS

摘要

The Moessbauer spectra of PdMn_xFe_(1-x) alloys obtained at 80 K and at 300 K were studied in the 0.2 < x < 0.8 concentration range, in which there realizes a microinhomogeneous multiphase medium formed by isostructure phases of the constituent compositions: ferromagnetic PdFe (T_c=730 K) alloy undergoing atomic ordering and antiferromagnetic PdMn (T_N = 815 K) intermetallic compound. Magnetic properties studies evidence the presence of a third presumably noncollinear phase with its own ordering temperature lying below the Curie temperature of the ferromagnetic phase in the 0.2 < x < 0.8 concentration range. The Mossbauer spectra at 300 K exhibit a doublet for antiferromagnetic alloys (x > 0.8) and a sextet at H_(hf) ～350 kOe for ferromagnetic alloys (x < 0.2). In the intermediate concentration range several peaks 0 < H_(hf) < 350 kOe have been observed in the P(H_(hf)) curves, which result from microinhomogeneous multiphase state.