Extended Data Fig. 5: Spectra above and next to a pentacene molecule.

a, AFM topography image of a surface area with adsorbed pentacene molecules measured with a CO-terminated tip (set point: Δf = −1.45 Hz at V = 0 V, A = 1.65 Å). The inset shows a constant-height AFM image as a zoom-in (A = 0.3 Å, Δz = −4.76 Å with respect to the set point Δf = −1.45 Hz at V = 0 V, A = 0.3 Å). b, ESR-AFM spectra above (blue) and next to (red) the pentacene-d₁₄ molecule shown in a (error bars are s.d. of four repetitions). Although the former shows a clear feature around 1,540 MHz, this feature is absent for the spectrum acquired next to the molecule. For a discussion of the spatial confinement of the ESR-AFM signal, see the main text. Note that the frequency shift was not normalized for these spectra.