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arXiv · 1207.3075

Nuclear Tunnelling and Dynamical Jahn-Teller Effect in Graphene with Vacancy

Z. S. Popović·B. R. K. Nanda·S. Satpathy
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Abstract

We show that the substitutional vacancy in graphene forms a dynamical Jahn-Teller center. The adiabatic potential surface resulting from the electron-lattice coupling was computed using density-functional methods and subsequently the Schr\"odinger equation was solved for the nuclear motion. Our calculations show a large tunnelling splitting $3 \Gamma$ of about 86 cm$^{-1}$. %, which is large as compared to the typical strain splitting. The effect results in a large delocalization of the carbon nuclear wave functions around the vacancy leading to a significant broadening of the Jahn-Teller active $sp^2\sigma$ electron states. The tunnelling splitting should be observable in electron paramagnetic resonance and two-photon resonance scattering experiments.

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Z. S. Popović, B. R. K. Nanda, S. Satpathy. 2012-07-12. Nuclear Tunnelling and Dynamical Jahn-Teller Effect in Graphene with Vacancy. https://doi.org/10.1103/physrevb.86.085458

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