Radical are atoms with unpaired electrons, and they have short lifetimes because the unpaired electrons are highly chemically reactive. The $$\ce{H2O^{.+}}$$ radical is named oxoniumyl. Is there a name for a hypothetical $$\ce{H2O^{.-}}$$ radical?
• $\ce{H2O^{.-}}$ does not exist. – Mathew Mahindaratne Jun 25 '20 at 15:01
• There is gas-phase hydrated radical anion $\ce{(H2O)_n^{.-}}$. I don't know if the anion exist for n=1. – Nilay Ghosh Jun 25 '20 at 16:21