Superoxide

Superoxide

Lewis structure of superoxide. The six outer-shell electrons of each oxygen atom are shown in black; one electron pair is shared (middle); the unpaired electron is shown in the upper-left; and the additional electron conferring a negative charge is shown in red.
Names
IUPAC name
Superoxide
Systematic IUPAC name
Dioxidan-2-idylide
Other names
Hyperoxide, Dioxide(1−)
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
487
KEGG
UNII
  • InChI=1S/O2/c1-2/q-1
    Key: MXDZWXWHPVATGF-UHFFFAOYSA-N
  • O=[O-]
Properties
O−2
Molar mass 31.998 g·mol−1
Conjugate acid Hydroperoxyl
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

In chemistry, a superoxide is a compound that contains the superoxide ion, which has the chemical formula O−2.[1] The systematic name of the anion is dioxide(1−). The reactive oxygen ion superoxide is particularly important as the product of the one-electron reduction of dioxygen O2, which occurs widely in nature.[2] Molecular oxygen (dioxygen) is a diradical containing two unpaired electrons, and superoxide results from the addition of an electron which fills one of the two degenerate molecular orbitals, leaving a charged ionic species with a single unpaired electron and a net negative charge of −1. Both dioxygen and the superoxide anion are free radicals that exhibit paramagnetism.[3] Superoxide was historically also known as "hyperoxide".[4]

  1. ^ Hayyan, M.; Hashim, M.A.; Al Nashef, I.M. (2016). "Superoxide Ion: Generation and Chemical Implications". Chem. Rev. 116 (5): 3029–3085. doi:10.1021/acs.chemrev.5b00407. PMID 26875845.
  2. ^ Sawyer, D. T. Superoxide Chemistry, McGraw-Hill, doi:10.1036/1097-8542.669650
  3. ^ Cite error: The named reference Valko was invoked but never defined (see the help page).
  4. ^ Hayyan, Maan; Hashim, Mohd Ali; Alnashef, Inas M. (2016). "Superoxide Ion: Generation and Chemical Implications". Chemical Reviews. 116 (5): 3029–3085. doi:10.1021/acs.chemrev.5b00407. PMID 26875845.