Oxygen dioxygenyl cation

Oxygen has an oxidation number of +2 in some fluorides [25,] which also stabilize the dioxygenyl cation 02" " [26], redox states which are not stable, of course, in solutions. The common redox reactions... 

Dioxygenyl is preferred to dioxygenium, to indicate the removal of one electron from dioxygen (O2) since the suffix -yl is usual for cations or radicals containing oxygen e.g., nitrosyl and chlorosyl), whereas -ium is often used to indicate the addition of a proton. 

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