Just as the RI approximation performs well for energy differences despite absolute errors that grow with system size, it is not immediately clear whether larger DLPNO errors (as a function of system size) will manifest as larger errors in ∆E. Thus, we next consider a sequence of increasingly large polybenzenoid dimers in the circumcoronene family, ranging from (C 6 H 6 ) 2 up to (C 96 H 24 ) 2 . DLPNO errors for these dimers, evaluated at the RI-MP2/cc-pVDZ level, are plotted in Fig. . Accumulation of error with respect to system size is especially evident for the two larger systems.