Cl2Cl

Cl2Cl is not a standard chemical formula used for a well-characterized compound. In most chemical references, the exact string "Cl2Cl" does not designate a discrete, isolable substance. As a result, its meaning depends on context and may refer to one of several transient or misnotated species in chlorine chemistry.

One possible interpretation is that Cl2Cl denotes a chlorine trimer (three chlorine atoms bonded in a cluster), i.e., a Cl3 species or Cl3• radical. Such species can appear transiently in gas-phase chlorine chemistry, particularly during photolysis or reactions involving Cl2 and Cl, but they are not stable under standard conditions and are rarely isolated.

Another common reading is that it is a shorthand or typographical error for a known compound with a similar name, such as chlorine dichloride (Cl2Cl2) or chlorine monochloride (ClCl), both of which are interhalogen relationships where chlorine forms covalent bonds with another chlorine or halogen atom. These species are better represented by their standard formulas (Cl2, ClCl, and Cl2Cl2) and have distinct reactivity.

Because chemical notation can vary, sources using Cl2Cl should be consulted directly to understand the intended meaning. In general, Cl2Cl has no widely recognized, standalone identity in mainstream inorganic chemistry.