Figure 6.

Sample containing the NO–NO and the Gd–Gd rulers mixed in a $\mathrm{1}:\mathrm{2}$ molar ratio. The legend is the same as in Fig. . The form factors in the NOGd and in the GdGd channel were fitted using both a single Gaussian (solid line) and two Gaussians (broken line) to highlight the appearance of a spectrometer artifact corresponding to a 3.5 nm distance (highlighted with an asterisk; see Fig. S8; part B). The NOGd DEER channel contains a Gd–Gd crosstalk signal in the absence of a NO–Gd distance designated as  $X_{\mathrm{2}}$ . A comparison of how different neural networks fit this crosstalk signal is shown in Fig. S9a (part B).