Symmetry adapted perturbation theory partitioning

Contrary to the previously described supermolecular approach, perturbation theory treatment allows for the partition of the interaction energy into physically interpretable components. The most frequently used method for this purpose is symmetry-adapted perturbation theory (SAPT) [13]. More recently, great effort has also been invested in the development of DFT-SAPT [14-16], In the present contribution, we use the variational-perturbational scheme [17-20], In this approach, the intermolecular interaction energy components are determined based on the wave functions of the subsystems evaluated in the dimer-centered basis set. Thus, both interaction energy and its components are BSSE-free. More details about this scheme can be found elsewhere [21-23]. The total intermolecular interaction energy at the MP2 level of theory can be expressed as follows ... 

SAPT Symmetry-Adapted Perturbation Theory. A means of partitioning the interaction energy into various components. 

Atomic-Partitioned Symmetry-Adapted Perturbation Theory... 

Parrish, R. M., and Sherrill, C. D. (2014). Spatial assignment of symmetry adapted perturbation theory interaction energy components The atomic SAPT partition, J. Chem. Phys. 141, p. 044115, doi 10.1063/1.4889855. 

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