Hydroxyl radical

Neutral form of the hydroxide ion

The hydroxyl radical, denoted as HO• or •OH, is the neutral form of the hydroxide ion (OH–). As a free radical, it is highly reactive and consequently short-lived, making it a pivotal species in radical chemistry. In nature, hydroxyl radicals are most notably produced from the decomposition of hydroperoxides (ROOH) or, in atmospheric chemistry, by the reaction of excited atomic oxygen with water.

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