We develop an ab initio framework that captures the impact of electron-electron and electron-hole interactions on phonon properties. This enables the inclusion of excitonic effects in the optical phonon dispersions and lifetimes of graphene, both near the center ($\mathrm{\Gamma }$) and at the border ($K$) of the Brillouin zone, at phonon-momenta relevant for Raman scattering and for the onset of the intrinsic electrical resistivity. Near $K$, we find a phonon redshift of $\sim 150{\mathrm{cm}}^{-1}$ and a $10\times$ enhancement of the group velocity, together with a $5\times$ increase in linewidths due to a $26\times$ increase of the electron-phonon matrix elements. These effects persist for doping $2E_F<\hslash {\omega }_{\mathrm{ph}}$ and are quenched at higher dopings. Near $\mathrm{\Gamma }$, the excitonic effects are minor because of the gauge field nature of the electron-phonon coupling at small phonon momentum.

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• Bethe-Salpeter equation
• Electron-phonon coupling
• Electronic structure
• Phonons
• 2-dimensional systems
• Graphene
• Density functional calculations
• Hybrid functionals
• Tight-binding model