In chemistry, a lyate ion is the anion derived by the deprotonation of a solvent molecule.[1] For example, a hydroxide ion is formed by the deprotonation of water, and methoxide is the anion formed by the deprotonation of methanol.
Its counterpart is a lyonium ion, the cation formed by the protonation of a solvent molecule.
Lyonium and lyate ions, resulting from molecular autoionization, contribute to the molar conductivity of protolytic solvents.