Chlorine is always found to be as the diatomic gas, i.e., Cl2. So, to get Cl atom alone, it is said to be in fission. Homolytic fission is a process, in which the Cl atom is alone can be get back from the Cl2 gas, not as an anion or a cation, it can be taken as an atom.
So, while doing experiments u'll be taking only Cl2. C;l cannot be stored separately.
It will either fuse with other metals, or it will fuse with other Chlorine atom.
Hope this will help you.