The first basicity scale of fluoro-, chloro-, bromo- and iodo...
Comparison with the basicity of group 15 and 16 elements shows that halogens are very weak bases, in the order: N O > P > S > Se > F > Cl ≈ Br ≈ I. Attempts at correlations of pKHBvs. electronegativity or vs. hardness lead to general scatter...