Magnetic and Electric Properties of Chalcopyrite

The torque of a natural single crystal of chalcopyrite in a uniform magnetic field is measured. At room temperature and liquid nitrogen temperature the torque of a disc parallel to (110)-plane shows two-fold symmetry and the easy direction is [110]. The temperature dependence of the torque is also measured. The torque vanishes at 550°C. Two principal susceptibilities parallel and perpendicular to c-axis, χ // and χ ⊥ , are calculated from the torque and the powder susceptibility. The conductivity, the Hall coefficient and their temperature dependences and the thermoelectric power are also measured. Their behaviours are those of typical semiconductors. Hall mobility and thermoelectric power are rather large, although chalcopyrite contains transition element, Fe, in its chemical foumula. The crystal structure, the electronic states of constituent elements, magnetic and electric properties are considered together, and it is concluded that the 3d-shell in this material is independent of the valence bond which consists of s p 3 bond.