The preparation and electrical properties of NiSexS2−x pyrites

Crystals of the NiSe_xS_2?x pyrite solid solution series were prepared by chemical transport with Cl₂. With increasing temperature, resistivity increases sharply in compositions with 0.47 ≤ x ≤ 0.54. The transition temperature increases with x from 30K to 100K. Disagreement is found with recently reported polycrystalline data.