AvH

Importance of the Exchange-Repulsion Energy in molecular interactions

01/07/2023 to 31/12/2024

In a recent paper we have demonstrated that the energy contribution of repulsive exchange-repulsion interactions has a previously unrecognized but significant influence on the intermolecular interaction energy; it is the repulsive interaction appearing when occupied molecular orbitals overlap. The exchange-repulsion is an original quantum mechanical effect related to the antisymmetry requirement of electronic wavefunctions. We have also shown that it can be partitioned in contributions of orbital-pairs of the interacting systems. In the present project we plan to rationalizes this contribution to the interaction energy with a pictorial model resembling the frontier orbital method for a couple of characteristic cases such as aggregates of aromatic molecules, donor-acceptor systems and halogen bonds.