Singlet oxygen

Oxygen with all of its electrons spin paired

Singlet oxygen, systematically named dioxygen(singlet) and dioxidene, is a gaseous inorganic chemical with two oxygen atoms in a quantum state where all electrons are spin-paired, known as a singlet state. It is the lowest excited state of the diatomic oxygen molecule, which in general has the chemical structure O=O and chemical formula O2. Singlet oxygen can be written more specifically as 1[O2] or 1O2.

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