Electrical properties of natural and synthetic pyrite (FeS₂) crystals

We have prepared a series of syntheticn-type pyrite (FeS₂) crystals by chemical vapor transport and high temperature solution growth. These and natural crystals were characterized with respect to Hall mobility, carrier concentration, and conductivity, and chemically analyzed by mass spectroscopy and atomic emission spectroscopy. The results are compared in detail to previous work on natural crystals. Conductivity and carrier concentration in our measurements varied between 0.05 and 3.5 (Ω cm)⁻¹and between 6.9·10¹⁵and 5.4·10¹⁷cm⁻³, respectively. The peak mobilities have values ranging from 100 to 2000 cm²/Vs. We find that sulfur deficiency and a number of impurity elements, such as Si, Cu, and Al, can qualitatively account for the trends in the electronic properties.