Which among of the following Lithium halide is most covalent in nature?
LiF
LiCl
LiBr
LiI
The ion is very small in size and has high tendency to distort electron cloud around the anions. Due to large anionic size among other halides, polarizability of iodide ion is highest. According to Fajan's rules, higher the polarization, higher is the covalent character. Thus, Lithium iodide has highest covalent character among Lithium halides.