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Tight-binding approach to penta-graphene.

ABSTRACT: We introduce an effective tight-binding model to discuss penta-graphene and present an analytical solution. This model only involves the ?-orbitals of the sp(2)-hybridized carbon atoms and reproduces the two highest valence bands. By introducing energy-dependent hopping elements, originating from the elimination of the sp(3)-hybridized carbon atoms, also the two lowest conduction bands can be well approximated - but only after the inclusion of a Hubbard onsite interaction as well as of assisted hopping terms. The eigenfunctions can be approximated analytically for the effective model without energy-dependent hopping elements and the optical absorption is discussed. We find large isotropic absorption ranging from 7.5% up to 24% for transitions at the ?-point.

SUBMITTER: Stauber T

PROVIDER: S-EPMC4778137 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Tight-binding approach to penta-graphene.

Stauber T T Beltrán J I JI Schliemann J J

Scientific reports 20160304

We introduce an effective tight-binding model to discuss penta-graphene and present an analytical solution. This model only involves the π-orbitals of the sp(2)-hybridized carbon atoms and reproduces the two highest valence bands. By introducing energy-dependent hopping elements, originating from the elimination of the sp(3)-hybridized carbon atoms, also the two lowest conduction bands can be well approximated - but only after the inclusion of a Hubbard onsite interaction as well as of assisted ...[more]

PMID: 26940279

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