Fig. 6: Vibration modes of the framework during Li intercalation.

a Representative vibration modes predicted by phonons using first-principles calculations. Gray, red, and pink spheres represent C, O, and H, respectively. b Raman spectra for each fully lithiated sample. Detailed experimental and computational Raman spectra and other vibration modes are shown in Supplementary Figs. 24 and 25, respectively.