Nitryl

File:Nitrogen-dioxide-2D-dimensions-vector.svg

Nitryl is the nitrogen dioxide (NO₂) moiety when it occurs in a larger compound as a univalent fragment. Examples include nitryl fluoride (NO₂F) and nitryl chloride (NO₂Cl).{{Cite book|url=https://www.iupac.org/fileadmin/user_upload/databases/Red_Book_2005.pdf|title=Nomenclature of Inorganic Chemistry IUPAC Recommendations 2005|publisher=IUPAC|year=2005|access-date=2018-11-27|archive-url=https://web.archive.org/web/20141222172055/http://www.iupac.org/fileadmin/user_upload/databases/Red_Book_2005.pdf|archive-date=2014-12-22|url-status=dead}}

Like nitrogen dioxide, the nitryl moiety contains a nitrogen atom with two bonds to the two oxygen atoms, and a third bond shared equally between the nitrogen and the two oxygen atoms. The nitrogen-centred radical is then free to form a bond with another univalent fragment (X) to produce an N−X bond, where X can be F, Cl, OH, etc.

In organic nomenclature, the nitryl moiety is known as the nitro group. For instance, nitryl benzene is normally called nitrobenzene (PhNO₂).{{Cite book|title=A guide to IUPAC nomenclature of organic compounds: Recommendations 1993|author1=International Union of Pure and Applied Chemistry, Commission on the Nomenclature of Organic Chemistry|date=1993|publisher=Blackwell Scientific Publications|others=Panico, Robert; Powell, Warren H.; Richer, Jean-Claude|isbn=0632037024|location=Oxford|oclc=27431284}}