Iodine dioxide

This article is about the compound IO2. For the oxoanion with the formula IO−, see hypoiodite. For the molecule I2O, see Diiodine monoxide. For the animated film abbreviated "IO2", see Inside Out 2.
Iodine dioxide
Names
Other names
dioxidoiodide, iodyl, iodoxy radical, iodine peroxide, iodine superoxide
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
404604
  • InChI=1S/IO2/c2-1-3
    Key: WXDJHDMIIZKXSK-UHFFFAOYSA-N
  • O=I[O]
Properties
IO2
Molar mass 158.902 g·mol−1
Appearance yellow solid
Density 4.2 g/cm3
Melting point 130 °C (266 °F; 403 K)
reacts with water
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Iodine dioxide is a binary inorganic compound of iodine and oxygen with the chemical formula IO
2.[1][2] Only stable as a dilute gas,[3] this compound is one of many iodine oxides,[4][5] and "iodine dioxide" is sometimes used to describe its formal dimer, the salt diiodine tetroxide (I2O4, [IO]+[IO3]−).

It is formed, in parts-per-trillion quantities,[6] at the marine boundary layer and believed to mediate particulate nucleation therein. The iodine, originally from algaeic diiodomethane, is photooxidized to iodine monoxide, which then disproportionates to free iodine atoms and iodine dioxide. At a sufficiently large concentration, the particles then combine to form small grains of diiodine tetroxide.[3][7]

  1. ^ Yaws, Carl (6 January 2015). The Yaws Handbook of Physical Properties for Hydrocarbons and Chemicals: Physical Properties for More Than 54,000 Organic and Inorganic Chemical Compounds, Coverage for C1 to C100 Organics and Ac to Zr Inorganics. Gulf Professional Publishing. p. 718. ISBN 978-0-12-801146-1. Retrieved 10 May 2023.
  2. ^ Haynes, William M. (19 April 2016). CRC Handbook of Chemistry and Physics. CRC Press. p. 2-17. ISBN 978-1-4398-8050-0. Retrieved 10 May 2023.
  3. ^ a b Hoffmann, Thorsten; O'Dowd, Colin D.; Seinfeld, John H. (15 May 2001). "Iodine oxide homogeneous nucleation: An explanation for coastal new particle production" (PDF). Geophysical Research Letters. 28 (10): 1949–1952. Bibcode:2001GeoRL..28.1949H. doi:10.1029/2000GL012399.
  4. ^ De, Anil Kumar (2007). A Textbook Of Inorganic Chemistry. New Age International. p. 584. ISBN 978-81-224-1384-7. Retrieved 10 May 2023.
  5. ^ Parks, Lytle Raymond (1952). Systematic College Chemistry. Blakiston Company. p. 304. Retrieved 10 May 2023.
  6. ^ Saiz-Lopez, A.; Fernandez, R. P.; Ordóñez, C.; Kinnison, D. E.; Gómez Martín, J. C.; Lamarque, J.-F.; Tilmes, S. (10 December 2014). "Iodine chemistry in the troposphere and its effect on ozone". Atmospheric Chemistry and Physics. 14 (23): 13119–13143. Bibcode:2014ACP....1413119S. doi:10.5194/acp-14-13119-2014. hdl:11336/100317.
  7. ^ Cox, R. A.; Bloss, W. J.; Jones, R. L.; Rowley, D. M. (1 July 1999). "OIO and the atmospheric cycle of iodine" (PDF). Geophysical Research Letters. 26 (13): 1857–1860. Bibcode:1999GeoRL..26.1857C. doi:10.1029/1999GL900439. S2CID 128402214.