  Systematic experimental (vibrating sample magnetometry) and theoretical
(electronic structure calculations using charge and spin self-consistent
Korringa-Kohn-Rostoker Green function method) studies were performed on a
series of intermetallic sigma-phase Fe(100-x)Re(x) (x = 43-53) compounds. Clear
evidence was found that all investigated samples exhibit magnetism with an
ordering temperature ranging between 65 K for x = 43 and 23 K for x = 53. The
magnetism was revealed to be itinerant and identified as a spin-glass (SG)
possibly having a re-entrant character. The SG was found to be heterogeneous
viz. two regimes could be distinguished as far as irreversibility in
temperature dependence of magnetization is concerned: (1) of a weak
irreversibility and (2) of a strong one. According to the theoretical
calculations the main contribution to the magnetism comes from Fe atoms
occupying all five sub lattices. Re atoms have rather small moments. However,
the calculated average magnetic moments are highly (ferromagnetic ordering
model) or moderately (antiparallel ordering model) overestimated relative to
the experimental data.
