# Dissociation energy of benzene dimer

It is known that the benzene dimer has two stable structures, T-shaped ($\ce{C_{2v}}$) or parallel-displaced ($\ce{C_{2h}}$) structure.

Now the question is: does the dissociation energy ($\ce{D_0}$) $$\ce{(C_6H_6)_2 -> C_6H_6 + C_6H_6}$$ depends on the structures? Or it is independent of the structures?

• Of course it has to depend, at least a bit... – Mithoron Apr 10 '18 at 23:27
• Of the three configurations mentioned by @rbw the parallel-displaced is most likely to be the most stable.; see chemistry.stackexchange.com/questions/60055/… and you can calculate these for yourself. – porphyrin Apr 11 '18 at 16:01

## 1 Answer

In fact you have three configurations to consider: t-shaped, parallel-displaced and sandwich. The dissociation energy depends on the configurations of the structures since they may interact differently. As the pi-pi interaction is directional, the different structures of the dimer interact differently.

• I think it would best if you elaborate a bit. Don't leave answers that require clarification from the asker. – M.A.R. Apr 11 '18 at 14:03