 | |
| Names | |
|---|---|
| Other names iodine trioxide, diiodine(V,VII) oxide | |
| Identifiers | |
3D model (JSmol) | |
| |
| |
| Properties | |
| I2O6 | |
| Molar mass | 349.803 g·mol−1 |
| Appearance | yellow crust or crystals |
| Density | 4.53 g/cm3[1] |
| Melting point | 179 °C (354 °F; 452 K) (dec.) |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Diiodine hexaoxide, is a chemical compound ofoxygen andiodine with the chemical formula I2O6. It belongs to the class ofiodine oxides, and is amixed oxide, consisting of iodine(V) and iodine(VII)oxidation states.
Reaction ofperiodic acid withiodic acid insulfuric acid:[2]
The thermal decomposition ofmeta-periodic acid in vacuum also leads to the formation of diiodine hexoxide.[2]
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.[citation needed] When heated above 179 °C, decomposition into diiodine pentoxide can be observed, with the reaction going to completion at 197 °C:[3]
Structurally, the compound is a polymeric iodine(V,VII) oxide consisting of repeating I4O12, units[1] contradicting previous sources describing it as "iodyl periodate" (IO2+IO4-).[2] As a solid, the compound crystallizes in the space groupP1 (space group no. 2) with the lattice constantsa = 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.[1]
Diiodine hexaoxide has been investigated for potential use as a neutralizer for chemical and biological agents in combination with aluminium powder.[3]