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arXiv · 1101.4007

Strength of effective Coulomb interactions in graphene and graphite

T. O. Wehling·E. Sasioglu·C. Friedrich·A. I. Lichtenstein·M. I. Katsnelson·S. Blügel
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Abstract

To obtain an effective many-body model of graphene and related materials from first principles we calculate the partially screened frequency dependent Coulomb interaction. In graphene, the effective on-site (Hubbard) interaction is U_00 = 9.3 eV in close vicinity to the critical value separating conducting graphene from an insulating phase emphasizing the importance of non-local Coulomb terms. The nearest-neighbor Coulomb interaction strength is computed to U_01 = 5.5 eV. In the long wavelength limit, we find the effective background dielectric constant of graphite to be ε= 2.5 in very good agreement with experiment.

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T. O. Wehling, E. Sasioglu, C. Friedrich, A. I. Lichtenstein, M. I. Katsnelson, S. Blügel. 2011-06-09. Strength of effective Coulomb interactions in graphene and graphite. https://doi.org/10.1103/physrevlett.106.236805

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