To decide between CC2 and SCS-CC2, we conduct a study DZ-, TZ-, and QZ-quality basis sets both with and without additional diffuse functions. This comparison involves both Ahlrichs [def2-nZVP(D)] 130,182 and Dunning [(aug-)cc-pVnZ] 183,184 basis sets; where n corresponds to 'S/D', 'T', 'Q', respectively. All dissociation curves are shown in Fig. including select points for CCSDR(3)/def2-TZVP near the minimum to allow for an initial evaluation. Note that due to its computational cost, generating complete dissociation curves with CCSDR(3) was technically not feasible. Numerical values for interaction energies and intermolecular distances at the respective curve minima are shown in Table . It is obvious that all CC2 minima-regardless of the basis setare deeper than the SCS-CC2 ones, meaning that CC2 consistently gives larger dissociation energies (Fig. ). CC2 results indicate systematic overstablisation, exhibiting dissociation energies that are almost twice as large as CCSDR(3). For instance, with the def2-TZVP basis set, the CCSDR(3) interaction energy at an intermolecular distance r of 3.00 Å (a point in proximity of the expected minimum for this level of theory) is -11.96 kcal/mol (Table † ) and the well depths of SCS-CC2 and CC2 are -13.18 kcal/mol (r e =2.99 Å) and -20.19 kcal/mol (r e =2.90 Å), respectively. While the differences between CC2 and SCS-CC2 are quite striking, the general trends show parallels to ground-state studies, where it has been established that conventional MP2 overestimates interaction energies in dispersion-driven complexes, while SCS-MP2 provides a more balanced description. ,128 CC2 has also been shown to overestimate the dispersion contribution in the same excimer complexes as studied here and it appears, by its closer proximity to CCSDR(3), that SCS-CC2 reduces this overestimation. Despite SCS-CC2 being in closer proximity to CCSDR(3), both CC2 variants across all basis sets explored overstabilise the excimer relative to CCSDR(3)/def2-TZVP.