Nonstoichiometric lead dioxides

It is generally believed that lead dioxide has semiconductor properties. Actually, the atomic ratio between lead and oxygen is not 1 2 like that in the Pb02 formula. In this case, a formula of PbO can be used to indicate this molecule is not stoichiometric instead, it is nonstoichiometric. Furthermore, there are amorphous PbO variants except a-Pb02 and p-Pb02. Differential thermal analysis (DTA), x-ray, and nuclear... 

---