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arXiv · 2104.11065

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

Arpan Kundu·Marco Govoni·Han Yang·Michele Ceriotti·Francois Gygi·Giulia Galli
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Abstract

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.

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Arpan Kundu, Marco Govoni, Han Yang, Michele Ceriotti, Francois Gygi, Giulia Galli. 2021-04-22. Quantum vibronic effects on the electronic properties of solid and molecular carbon. https://doi.org/10.1103/physrevmaterials.5.l070801

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