Using MO theory predict which of the following species has the shortest bond length ?
Using MO theory predict which of the following species has the shortest bond length ?
$\mathrm{O}_2^{2+}$
$\mathrm{O}_2^{+}$
$\mathrm{O}_2^{-}$
$\mathrm{O}_2^{2-}$
Solution
Bond length $\alpha \frac{1}{\text { bond order }}$
Bond order $=\frac{\text { no..of bonding } \overline{\mathrm{e}}-\text { no.of antibonding } \overline{\mathrm{e}}}{2}$
Bond orders of $\mathrm{O}_2^{+}, \mathrm{O}_2^{-}, \mathrm{O}_2^{-2}$ and $\mathrm{O}_2^{+2}$ are respectively $2.5,1.5,1$ and 3 .