Protactinium monoxide

Protactinium monoxide is a radioactive inorganic compound and one of the oxides of protactinium. Its chemical formula is PaO. It is a black solid that crystallizes in the rock-salt structure. Protactinium monoxide can be produced in minute quantities from the oxidation of protactinium. The protactinium monoxide cation (PaO+) is very active and can activate hydrocarbons such as alkenes.