Exercise 10 | Bonding Theories

Use molecular orbital theory to explain why argon does not form a stable diatomic molecule under normal conditions.

The theoretical molecular orbital diagram of Ar2 is similar to that of Ne2 using 3s and 3b AOs instead of 2s and 2p.


Ground state electron configuration of Ar2:

1s)2(σ*1s)22s)2(σ*2s)22p)22p)4(π*2p)4(σ*2p)23s)2(σ*3s)23p)23p)4(π*3p)43p)2


Bond order = 18-182 = 0 ⇒ Ar2 does not exist under normal conditions.