Editing Stereocenter (section)

{{Short description|Atom which is the focus of stereoisomerism in a molecule}}
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[[File:Chirality with hands.svg|upright=1.3|thumb|Two [[enantiomer]]s of a generic [[amino acid]] at the stereocenter]]

In [[stereochemistry]], a '''stereocenter''' of a [[molecule]] is an [[atom]] (center), axis or plane that is the focus of [[stereoisomerism]]; that is, when having at least three different groups bound to the stereocenter, interchanging any two different groups creates a new [[stereoisomer]].<ref name=":1">{{Cite web | url = https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map%3A_Organic_Chemistry_(Smith)/Chapter_05%3A_Stereochemistry/5.04_Stereogenic_Centers | title = 5.4: Stereogenic Centers | website = libretexts.org| date = April 24, 2015 }}</ref><ref name="Mislow&Siegel 1984">{{Cite journal |last1=Mislow |first1=Kurt |last2=Siegel |first2=Jay |year=1984 |title=Stereoisomerism and local chirality |journal=Journal of the American Chemical Society |volume=106 |issue=11 |pages=3319 |doi=10.1021/ja00323a043|bibcode=1984JAChS.106.3319M }}</ref> Stereocenters are also referred to as '''stereogenic centers'''. 

A stereocenter is geometrically defined as a point (location) in a molecule; a stereocenter is usually but not always a specific atom, often carbon.<ref name="Mislow&Siegel 1984" /><ref name="solomons">{{Cite book | first1= T. W. Graham |last1= Solomons| first2= Craig | last2= Fryhle| publisher= John Wiley & Sons| year= 2004 | title = Organic Chemistry | edition = 8th }}{{page needed| date= February 2016}}</ref> Stereocenters can exist on [[Chirality (chemistry)|chiral]] or [[achiral]] molecules; stereocenters can contain single bonds or double bonds.<ref name=":1" /> The number of hypothetical stereoisomers can be predicted by using 2<sup>''n''</sup>, with ''n'' being the number of [[Tetrahedral molecular geometry|tetrahedral]] stereocenters; however, exceptions such as [[Meso compound|meso compounds]] can reduce the prediction to below the expected 2<sup>''n''</sup>.<ref name=":3" /> 

[[Chirality (chemistry)|'''Chirality centers''']] are a type of stereocenter with four different substituent groups; chirality centers are a specific subset of stereocenters because they can only have sp<sup>3</sup> hybridization, meaning that they can only have [[Sigma bond|single bonds]].<ref name=":2" />