Tellurium‐Rich Tellurides

Abstract The tellurides represent a class of compounds which exhibit a wide range of physical and chemical properties. In addition to the salt‐like compounds, some tellurides show metallic properties while others have strong covalent bonds. Like tellurium itself, many of these are semiconductors, e.g., the II‐VI compounds CdTe and MnTe, and in this respect are of special interest. Other tellurides, e.g., NbTe 4 and ZrTe 5 , have low‐dimensional electronic transport properties. Some ternary transition metal‐main group metal tellurides appear in an amorphous state with spin glass properties. The tellurium‐rich tellurides are characterized without exception by directed Te‐Te bonds. It turns out that general structural chemical relationships exist between them which allow these different compounds to be treated as a single comprehensive class of substances. They represent a link between the Zintl phases on the one hand, and molecular compounds on the other.