Several polycrystalline samples of the half-Heusler alloy NiMnSb were grown by arc melting
of stoichiometric and nonstoichiometric amounts of high-purity constituent elements. The
structure and the phase-purity of the prepared samples were examined systematically by
powder x-ray diffraction. The transport properties of the best sample, with saturation
magnetization M s (5 K)= 4 μ B/formula unit, were studied by measuring electrical resistivity,
thermal conductivity, and thermopower. Features in both magnetic and transport data are …