Quantum vibronic effects on the electronic properties of solid and molecular carbon

We study the effect of quantum vibronic coupling on the electronic properties of carbon allotropes, including molecules and solids, by combining path integral first principles molecular dynamics (FPMD) with a colored noise thermostat. In addition to avoiding several approximations commonly adopted in calculations of electron-phonon coupling, our approach only adds a moderate computational cost to FPMD simulations and hence it is applicable to large supercells, such as those required to describe amorphous solids. We predict the effect of electron-phonon coupling on the fundamental gap of amorphous carbon, and we show that in diamond the zero-phonon renormalization of the band gap is larger than previously reported.

Automated summary

The study investigates the impact of quantum vibronic coupling on the electronic properties of carbon allotropes, utilizing path integral first principles molecular dynamics combined with a colored noise thermostat. By avoiding common approximations and only adding a moderate computational cost to FPMD simulations, the approach is suitable for large supercells needed for describing amorphous solids. The research predicts the effect of electron-phonon coupling on the fundamental gap of amorphous carbon and reveals a larger zero-phonon renormalization of the band gap in diamond than previously reported.