Fine structure and chemical shifts in nonresonant inelastic x-ray scattering from Li-intercalated graphite

The authors report measurements of hard x-ray nonresonant inelastic x-ray scattering (IXS) from the Li and C 1s electrons of fully staged LiC6 Li-intercalated graphite prepared by both chemical and electrochemical methods. They find that the Li 1s orbital shifts to higher energies relative to Li metal. Relative to graphite, the C 1s IXS for LiC6 shows a shift for the σ-orbital threshold to lower energies, but no shift for the π* resonance. The findings provide bulk-sensitive evidence for substantial charge transfer from the Li intercalant to the carbon host and establish important groundwork for future in situ electrochemical studies.