# How would you expect the extent of overlap of atomic orbitals to vary in the series "IF", "ICI", "IBr", and "I"_2?

Apr 13, 2017

Well, for these interhalogens, you would expect that the order of overlap between atomic orbitals DECREASES down the group........

#### Explanation:

A priori, we would expect BETTER overlap, and stronger bonding, when the heteroatom is smaller (caution, the $F - F$ is disproportionately weak, and this is attributed to lone pair interaction between the fluorine atoms).

And thus, in terms of bonding interaction:

$I - F > I - C l > I B r > {I}_{2}$.

And how could we assess this? Well, one way could be the interhalogen bond strength.........And I would consult your inorganic chemistry text for actual values.