Electrical Properties of Molybdenite

The following electrical properties of natural crystals of MoS2 have been measured: conductivity, Hall coefficient and thermoelectric power over the temperature range - 183°C to 500°C, and the room temperature change of conductivity in a magnetic field. It was found that the majority of the specimens were p-type semiconductors. The variation of the mobility of the charge carriers with temperature has been derived and indicates that the scattering of the charge carriers is mainly due to thermal vibrations of the lattice except at low temperatures when impurity scattering becomes important. Reasonable agreement is obtained between the values of the mobility calculated from the change in conductivity in a magnetic field, and from Hall coefficient and conductivity measurements. The results of the thermoelectric power measurements, and the variation of the concentration of charge carriers derived from the Hall coefficient are discussed and compared with theory.