Chlorine tetroxide

Chlorine tetroxide
Names
	IUPAC name Tetraoxidochlorine
Identifiers
CAS Number	12133-63-0 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:29420;
ChemSpider	4574089;
Gmelin Reference	239881
PubChem CID	5460591;
	InChI InChI=1S/ClO4/c2-1(3,4)5 Key: UXZQWBXGIHHEHG-UHFFFAOYSA-N;
	SMILES O=Cl(=O)(=O)[O];
Properties
Chemical formula	ClO4
Molar mass	99.45 g mol−1
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chlorine tetroxide is an unstable chlorine oxide with the chemical formula ClO₄.

History

Gomberg's mistaken 1923 production

In 1923, chemist Moses Gomberg proposed a production method of chlorine tetroxide. He claimed that treating iodine and silver perchlorate in anhydrous diethyl ether produced it.^[2]

I₂ + 2 AgClO₄ → 2 AgI + (ClO₄)₂

However, later researchers claimed that the product was iodine perchlorate.^[3] So far, however, there is no certain evidence for the existence of iodine perchlorate either.

Eachus' 1968 production

In 1968, Eachus synthesized it by exposing potassium chlorate to gamma rays at 77 K. It is a reaction intermediate of the decomposition of dichlorine heptoxide.^{[citation needed]}

Properties

The electron affinity energy of chlorine tetroxide can be figured out using the Born–Haber cycle and the lattice energy data of perchlorates. It is about 561 kJ/mol.^[4]

The structure of chlorine tetroxide is uncertain; the molecular point group may be C_s, C_2v, or T_d.^[5]

In a solid oxygen matrix ClO₄ reacts to form ClO₆Cl, which has three double bonded oxygen atoms, and a chain of three oxygen atoms -O-O-O^• attached to the chlorine.^[5]

References

^ "Perchloryloxy". Active Thermochemical Tables.
^ Gomberg, M. (1 February 1923). "The Reaction Between Silver Perchlorate and Iodine. Chlorine Tetra-Oxide". Journal of the American Chemical Society. 45 (2): 398–421. doi:10.1021/ja01655a017.
^ Alcock, N. W.; Waddington, T. C. (1 January 1962). "478. The reaction between iodine and silver perchlorate". Journal of the Chemical Society (Resumed): 2510. doi:10.1039/JR9620002510.
^ (in Chinese)张青莲 (1991). 《无机化学丛书》第六卷：卤素、铜分族、锌分族. 北京: 科学出版社. p. 272. ISBN 7-03-002238-6.
^ ^a ^b Kopitzky, Rodion; Grothe, Hinrich; Willner, Helge (16 December 2002). "Chlorine Oxide Radicals ClO_x (x=1–4) Studied by Matrix Isolation Spectroscopy". Chemistry: A European Journal. 8 (24): 5601–5621. doi:10.1002/1521-3765(20021216)8:24<5601::AID-CHEM5601>3.0.CO;2-Z. PMID 12693042.