Extended Data Fig. 1: XRD images of hexagonal graphite at different pressures before and after transition.
a, 13.2 GPa. b, 20.0 GPa. The incident X-ray beam is parallel to the c-axis of pristine graphite. The graphite (\(10\bar{1}0\)) and (\(11\bar{2}0\)) diffraction spots at 13.2 GPa and the corresponding spots appearing at 20.0 GPa are labelled by orange and green circles in a and b, respectively. c–j, Evolution of the (\(11\bar{2}0\)) and (\(10\bar{1}0\)) diffraction spots under pressures between 13.2 GPa and 20.0 GPa. A fuzzy peak epitaxy to the graphite (\(10\bar{1}0\)) peak with a smaller d-spacing appears and grows at the expense of graphite (\(10\bar{1}0\)) from 14.9 GPa, whereas a similar evolution can be seen from the graphite (\(11\bar{2}0\)) peak but with a larger d-spacing from 17.4 GPa. At 20.0 GPa, both graphite (\(10\bar{1}0\)) and (\(11\bar{2}0\)) peaks disappear and the new peaks with d-spacings of 2.061 Å and 1.223 Å form completely.
