Oxygen singlet D atom
= Oxygen singlet D atom
{title2=$\mathrm O({}^1D)$}
An electronically excited atomic oxygen state produced in part by <ozone> <photodissociation>. Reaction with <water> can yield two <hydroxyl radicals>, while collisional quenching returns the atom to its triplet ground term without the same <radical> production. Its short-lived steady balance is distinct from the lifetime of <ozone> or <water>.