The metrics d CD1 , d CD2 , and d CD3 that were defined in eqs. 19-21 prove to be more useful as diagnostics, especially d CD1 . TD-DFT errors are plotted against these quantities in Fig. ; see Tables and for the data set. The d CD1 metric does the best job of separating the localized excitations from the Rydberg and CT transitions. The distribution of d CD1 values (Fig. ) closely resembles that of Γ NTO in Fig. , and from these data one might infer a trust radius of about 2 Å, which is the value put forward previously based on analysis of Γ NTO . As compared to the error distribution versus d e-h error / eV 1 ≈ 1 is satisfied by many (though not all) of the transitions in the data set used in Section 4 .2, which has also been used elsewhere to calibrate TD-DFT errors versus metrics such as Γ or Λ. The distribution of errors versus Γ NTO (Fig. ) strongly resembles the distribution versus d CD1 (Fig. ) for the examples in that data set.