Dichlorine hexoxide

Dichlorine hexoxide
IUPAC name

Dichlorine hexoxide
Other names

Chlorine(VI) oxide; Chlorine trioxide; Chloryl perchlorate
Identifiers
CAS number 12442-63-6 Y
Properties
Molecular formula Cl2O6
Molar mass 166.901 g/mol
Appearance red liquid
Density 1.65 g/cm3
Melting point

3.5 °C
Boiling point

200 °C
Solubility in water reacts with water
Hazards
Main hazards oxidizer
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Dichlorine hexoxide is the chemical compound with the formula Cl2O6. This chlorine oxide is the mixed anhydride of chloric and perchloric acids. It is produced by reaction between chlorine dioxide and excess ozone:

2 ClO2 + 2 O3 → 2 ClO3 + 2 O2 → Cl2O6 + 2 O2

It is a dark red fuming liquid at room temperature that crystallizes as an ionic compound, chloryl perchlorate, [ClO2]+[ClO4]−. It was originally reported to exist as the monomeric chlorine trioxide ClO3 in gas phase,[1] but was later shown to remain an oxygen-bridged dimer after evaporation and until thermal decomposition into chlorine perchlorate, Cl2O4, and oxygen.[2]

Properties

Cl2O6 is diamagnetic and is a very strong oxidizing agent. Although stable at room temperature, it explodes violently on contact with organic compounds[3] and reacts with gold to produce the chloryl salt [ClO2]+[Au(ClO4)4]−.[4] Many other reactions involving Cl2O6 reflect its ionic structure, [ClO2]+[ClO4]−, including the following:[5]

NO2F + Cl2O6 → NO2ClO4 + ClO2F
NO + Cl2O6 → NOClO4 + ClO2
2 V2O5 + 12 Cl2O6 → 4 VO(ClO4)3 + 12 ClO2 + 3 O2
SnCl4 + 6 Cl2O6 → [ClO2]2[Sn(ClO4)6] + 4 ClO2 + 2 Cl2

Nevertheless, it can also react as a source of the ClO3 radical:

2 AsF5 + Cl2O6 → 2 ClO3AsF5

References

  1. ^ C. F. Goodeve, F. A. Todd (1933). "Chlorine Hexoxide and Chlorine Trioxide". Nature 132 (3335): 514–515. doi:10.1038/132514b0. 
  2. ^ Lopez, Maria; Juan E. Sicre (1990). "Physicochemical properties of chlorine oxides. 1. Composition, ultraviolet spectrum, and kinetics of the thermolysis of gaseous dichlorine hexoxide". J. Phys. Chem. 94 (9): 3860–3863. doi:10.1021/j100372a094. 
  3. ^ Mary Eagleson (1994). Concise encyclopedia chemistry. Walter de Gruyter. p. 215. ISBN 3110114518. http://books.google.com/?id=Owuv-c9L_IMC. 
  4. ^ Cunin, Frédérique; Catherine Deudon, Frédéric Favier, Bernard Mula, Jean Louis Pascal (2002). "First anhydrous gold perchlorato complex: ClO2Au(ClO4)4. Synthesis and molecular and crystal structure analysis". Inorganic Chemistry 41 (16): 4173–4178. doi:10.1021/ic020161z. PMID 12160405. 
  5. ^ Harry Julius Emeléus, Alan George Sharpe (1963). Advances in Inorganic Chemistry and Radiochemistry. Academic Press. p. 65. ISBN 0120236052. http://books.google.com/?id=pRXIwIV-hB8C.