  Structural, electronic, and transport properties of ScNiSb, ScPdSb, and
ScPtSb were investigated from first principles. Electronic band structures
derived within the fully relativistic MBJLDA approach were compared with those
obtained from the standard GGA calculations. All the compounds studied exhibit
indirect narrow band gaps (0.24-0.63 eV). The effective masses of hole-like
carriers are relatively small (0.27-0.36), and decrease with an increasing
atomic number of the transition metal component. The carrier relaxation time,
required for realistic calculations of the electrical conductivity, was
approximated within the deformation potential theory. The GGA approach yielded
overestimated transport characteristics with respect to those derived within
the MBJLDA analysis. The largest power factor of 4-6 mWK^-2m^-1 ) at high
temperatures was obtained for ScPtSb. This value is comparable with those
observed experimentally for Fe-Nb-Sb half-Heusler alloys, and hence makes
ScPtSb a very good candidate material for thermoelectric applications.
