To isolate the dispersion energy, it is recommended 13 to compute ∆E FRZ using both the target functional (PBE0 + D3 in this case) and also with a "dispersionless" functional that is assumed to describe dispersion poorly or not at all (e.g., HF theory). The difference between ∆E FRZ computed with either functional Figure : Correlation between dispersion energies computed using either SAPT(LRC-ω GDD PBE) + MBD or ALMO-EDA2 applied to PBE0 + D3 (on the vertical axis) and benchmarks computed at the SAPT2+(3)/ aug-cc-pVTZ level (on the horizontal axis). For ALMO-EDA2, two different "dispersionless" XC functionals are examined for separation of E disp from ∆EFRZ via Eq. ( ). These are the same data as in Fig. . Adapted from Ref. 1; copyright 2024 Elsevier.