A Hirshfeld partitioning of the MP2 correlation energy: Method and its application to the benzene dimers

In this work a method is presented for the partitioning of MP2 correlation energies through a grid-space partitioning using the iterative Hirshfeld weight function. The correlation energies are partitioned into mono- and diatomic contributions using two alternative schemes, which allow different levels of parallelization. The method is tested on a set of 24 molecules containing various atoms, leading to the conclusion that, while the numerical results of the two schemes slightly differ, the chemical information contained in them is similar. The method is subsequently applied to the analysis of the interaction energy of three benzene dimers.