Diiodine hexaoxide, is a chemical compound of
oxygen and
iodine
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a vi ...
with the chemical formula I
2O
6. It belongs to the class of
iodine oxides, and is a
mixed oxide
In chemistry, a mixed oxide is a somewhat informal name for an oxide that contains cations of more than one chemical element or cations of a single element in several states of oxidation.Advanced Inorganic Chemistry, F. A. Cotton, G. Wilkinson ...
, consisting of iodine(V) and iodine(VII)
oxidation states.
Synthesis
Reaction of
periodic acid with
iodic acid
Iodic acid is a white water-soluble solid with the chemical formula . Its robustness contrasts with the instability of chloric acid and bromic acid. Iodic acid features iodine in the oxidation state +5 and is one of the most stable oxo-acids of ...
in
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
:
:
The thermal decomposition of ''meta''-periodic acid in vacuum also leads to the formation of diiodine hexoxide.
[
]
Chemical properties
Below 100 °C, diiodine hexaoxide can be stored stably in the absence of moisture. When dissolved in water, an exothermic reaction to form iodine and periodic acid takes place. When heated above 150 °C, decomposition into diiodine pentoxide can be observed:
:
The compound is diamagnetic, which is attributed to the different oxidation numbers of the iodine atoms.[ Structurally, the compound is iodyl periodate, an iodine(V,VII) oxide approximating IO2+IO4−.][ As a solid, the compound crystallizes in the space group ''P''1 (space group no. 2) with the lattice constants ''a'' = 500.6 pm, ''b'' = 674.1 pm, ''c'' = 679.5 pm, α = 97.1°, β = 96.43°, γ = 105.36° with one formula unit per unit cell.][
]
See also
* Diiodine tetroxide
* Orthoperiodic acid
* Diiodine pentoxide
Iodine pentoxide is the chemical compound with the Chemical formula, formula I2O5. This iodine oxide is the acid anhydride, anhydride of iodic acid, and the only stable oxide of iodine. It is produced by dehydrating iodic acid at 200 °C in ...
* Iodine oxides
References
* David R. Lide (Hrsg.): ''CRC Handbook of Chemistry and Physics
The ''CRC Handbook of Chemistry and Physics'' is a comprehensive one-volume reference resource for science research. First published in 1914, it is currently () in its 103rd edition, published in 2022. It is sometimes nicknamed the "Rubber Bible ...
96. Auflage. CRC Press / Taylor and Francis, Boca Raton FL, Properties of the Elements and Inorganic Compounds, S. 4-67.''
*
{{Iodides
Iodine compounds