Organophosphate
Organophosphates (also known as phosphate esters) are a class of organophosphorus compounds with the general structure O=P(OR). They can be considered as esters of phosphoric acid. Like most functional groups organophosphates occur in a diverse range of forms, with important examples including key biomolecules such as DNA, RNA and ATP, as well as many insecticides, herbicides, and nerve agents.
Phosphine oxide
Phosphine oxides are phosphorus compounds with the formula OPX. When X = alkyl or aryl, these are organophosphine oxides. Triphenylphosphine oxide is an example. An inorganic phosphine oxide is phosphoryl chloride (POCl). Such compounds are thermally stable, decomposing only above 450 °C. Phosphoryl refers to a functional group drawn with a phosphorus-oxygen double bond.