- Among the alkali metal ions, Li+ ion is the smallest cation while among halides, anion I- has the largest size.
- Thus, electron cloud around I- ion is easily distorted by Li+ ion leading to polarisation of anion and covalency.
- Also, the difference in electronegativities of Li and I is small.
Hence, lithium iodide is most covalent in nature among alkali halides.
