Figure 4

(a–c) images of carbon fibres: (a) high resolution image obtained with the electron microscope JSM 6400 from the National Centre of Microscopy of Spain; (b) optical  microscope image of a fibre before irradiation and (c) after irradiation. The results from the X-ray diffraction measurements with CHESS are displayed in (d–f): (d) schematic drawing of the experimental geometry; (e) X-ray pole figure collected at the scattering angle corresponding to the diamond (1, 1, 1) Bragg peak [Q = 3.035–3.065 Å⁻¹]; (f) X-ray pole figure collected at the scattering angle corresponding to the diamond (2, 2, 0) Bragg peak [Q = 3.50–3.54 Å⁻¹]. The existence of well-defined Bragg peaks in (e) and (f) provides strong evidence of crystalline diamond in the irradiated fibres.