Electrical properties of α-MnS

Electrical data including thermoelectric power, Hall effect and resistivity on iodine-grown crystals of p-type α-MnS are reported. A study of the temperature dependences reveals that the conductivity occurs by holes in a 3d-band (Mn³⁺) and that the mobility of the holes is not thermally activated. Photoelectron spectra confirm the 3d character of the top of the valence band. Accurate analysis of the electrical data gives a satisfactory explanation of the extrinsic and intrinsic behaviour; the simultaneous presence of donors (substitutional iodine) and acceptors (manganese vacancies) is responsible for the observed phenomena.