# Existence of Dichlorine Pentoxide

I searched the net and a lot of books, but I was unable to find any information about dichlorine pentoxide.

1. Does dichlorine pentoxide($$\ce{Cl2O5}$$) exist?
2. If it doesn't exist, then why so?
3. If dibromine pentoxide and iodine pentoxide do exit, then why not dichlorine pentoxide?
• I've never heard of this site, but here it is with a couple example reactions for what it's worth ;) – airhuff Feb 10 '17 at 6:38
• Here, it says it is unknown at present. – Nilay Ghosh Feb 10 '17 at 11:41
• That is a pretty old book though (Published in 2001). – Prakhar Feb 10 '17 at 14:26
• Ok , for once lets agree that Dichlorine Pentoxide doesnt exist. Then why is that so? Dibromine pentoxide(en.wikipedia.org/wiki/Dibromine_pentoxide) and Iodine Pentoxide does exit, then why not Dichlorine Pentoxide? – Prakhar Feb 10 '17 at 17:34
• I've seen this reaction given in half a dozen websites I've never heard of before: $\ce{Cl2O5 + H2O -> 2HClO3}$. The only one with any discussion is in Russian and I'm trying to find someone who can read that. It's just a couple sentences though. I've also seen it mentioned in nomenclature lessons, i.e. "$\ce{Cl2O5}$ chlorine dioxide from chloric oxide (V)" . Still nothing solid about it though. – airhuff Mar 1 '17 at 15:48

The crux of this (Russian) article is that $\ce{Cl2O5}$ is not stable enough to be isolated in a pure form, and if it were, it would be strongly acidic oxidizer.
$$\ce{NiCl2 + 3O2 -> NiO + Cl2O5}$$ $$\ce{H2O + Cl2O5 -> 2HClO3}$$
The statement in the first article and the simple fact that there is such a dearth of information about this compound suggest that it really only exists as a transient, unstable, oxidizing acid that apparently has not been isolated as a stable compound. Furthermore, information can be found in Wikipedia and/or PubChem for $\ce{Cl2O_x}$, where $x \in 1, 2, 3, 4, 6, 7$.