Editing Quaternary ammonium cation (section)

{{Short description|Polyatomic ions of the form N(–R)₄ (charge +1)}}
[[File:Quaternary ammonium cation.svg|thumb|right|Quaternary ammonium cation. The R groups may be the same or different [[alkyl]] or [[aryl]] groups. Also, the R groups may be connected.]]

In [[organic chemistry]], '''quaternary ammonium cations''', also known as '''quats''', are positively-charged [[polyatomic ion]]s of the structure {{chem2|[NR4]+}}, where R is an [[alkyl]] group, an [[aryl]] group<ref>{{GoldBookRef | file = Q05003 | title = quaternary ammonium compounds }}</ref> or [[organyl]] group. Unlike the [[ammonium|ammonium ion]] ({{chem2|NH4+}}) and the primary, secondary, or tertiary ammonium [[cations]], the [[Quaternary compound|quaternary]] ammonium cations are permanently charged, independent of the [[pH]] of their solution. '''Quaternary ammonium salts''' or '''quaternary ammonium compounds''' (called '''quaternary amines''' in [[oilfield]] parlance) are [[salt (chemistry)|salt]]s of quaternary ammonium cations. [[Polyquaternium|Polyquats]] are a variety of engineered [[polymer]] forms which provide multiple quat molecules within a larger molecule.

Quats are used in consumer applications including as [[antimicrobials]] (such as [[detergent]]s and [[disinfectant]]s), [[fabric softener]]s, and [[hair conditioner]]s. As an antimicrobial, they are able to inactivate [[viral envelope|enveloped viruses]] (such as [[SARS-CoV-2]]). Quats tend to be gentler on surfaces than [[bleach]]-based disinfectants, and are generally fabric-safe.<ref>{{Cite news | vauthors = Heffernan T |date = 14 April 2021 |title=The Best Surface Cleaners, Wipes, and Disinfectants|language=en-US|work=The New York Times|url=https://www.nytimes.com/wirecutter/reviews/best-all-purpose-cleaner/|access-date=2022-02-17|issn=0362-4331}}</ref>
[[File:OBINIXBu4N1.png|thumb|"Top" view of {{chem2|Bu4N+}} as determined by [[X-ray crystallography]].<ref name=Kern>{{cite journal | vauthors = Kern A, Näther C, Studt F, Tuczek F | title = Application of a universal force field to mixed Fe/Mo-S/Se cubane and heterocubane clusters. 1. Substitution of sulfur by selenium in the series [Fe4X4(YCH3)4]2-; X = S/Se and Y = S/Se | journal = Inorganic Chemistry | volume = 43 | issue = 16 | pages = 5003–5010 | date = August 2004 | pmid = 15285677 | doi = 10.1021/ic030347d }}</ref>]]
[[File:OBINIXBu4N2.png|thumb|"Side" view of {{chem2|Bu4N+}} as determined by X-ray crystallography.<ref name=Kern/>]]