LiF is least soluble among the fluorides of alkali metals, in LiF

smaller size ${\mathrm{Li}}^{+}$ impart significant covalent character in LiF

the hydration energies of ${\mathrm{Li}}^{+}\mathrm{and}{\mathrm{F}}^{-}$ are quite higher

lattice energy of LiF is quite higher due to the smaller size of ${\mathrm{Li}}^{+}\mathrm{and}{\mathrm{F}}^{-}$

LiF has strong polymeric network in solid