PDFGetX3 was used to obtain the S(q) and pair distribution function in G(r) space, with corrections for sample self-absorption, detector oblique incidence and Compton and Laue scattering. The q-range for the Fourier transform was qmin = 0.26 Å -1 to qmax =21.2 Å -1 . PDFgui was used to refine the G(r) for the pristine HCs and to simulate the G(r) for the different models. CeO2 was used as a calibrant and it was refined to obtain the qdamp=0.027 Å -1 and instrumentation broadening of qbroad=0.015 Å -1 from beamline (Figure ).