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The structural, electronic and magnetic behavior of the as-cast and annealed Mn₅₀Al₄₆Ni₄ and Mn₅₄Al₄₆ alloys was investigated. It was found that annealing at 470 °C promotes the formation of the τ phase in both alloys, however, all of the prepared samples were phase mixtures. The τ phase was found along with the κ phase (CsCl-type structure) only in the Mn₅₀Al₄₆Ni₄ alloy. M(T) curves show two transitions at 437 K and 634 K corresponding to the ferromagnetic κ and τ phases, respectively. A maximum τ phase content of 76 wt% for Mn₅₄Al₄₆ and 74 wt% for Mn₅₀Al₄₆Ni₄ was found for the samples annealed at 470 °C for 6 h. Saturation magnetization values at 4 K of 112 Am²/Kg and 106 Am²/Kg were obtained for Mn₅₄Al₄₆ and Mn₅₀Al₄₆Ni₄ respectively, in good agreement with the values reported in the literature. Band structure calculations show a preference for Ni to occupy the Mn 1a and 1c …