The data in Figure describe the degree to which the OR values converge with increasing basis set size for each choice of gauge and method. In these plots, the reference value used in Eq. 9 is the CBS(TQ) extrapolation for each gauge. For all methods, there is a clear decrease in total error compared to the reference values; the ∆ TQ U values (Eq. 10) with aug-cc-pVQZ are of the order of 0.01 for the DFT methods, panels (a) and (b), and 0.02-0.04 for CCSD, panel (c). Nonetheless, MVG results show a slightly slower convergence compared to the other choices of gauge.