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arXiv · 1402.5812

Electronic properties of linear carbon chains: resolving the controversy

Amaal Al-Backri·Viktor Zólyomi·Colin J. Lambert
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Abstract

Literature values for the energy gap of long one-dimensional carbon chains vary from as little as 0.2 eV to more than 4 eV. To resolve this discrepancy, we use the GW many-body approach to calculate the band gap $E_g$ of an infinite carbon chain. We also compute the energy dependence of the attenuation coefficient $β$ governing the decay with chain length of the electrical conductance of long chains and compare this with recent experimental measurements of the single-molecule conductance of end-capped carbon chains. For long chains, we find $E_g = 2.16$ eV and an upper bound for $β$ of $0.21$ Å$^{-1}$.

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Amaal Al-Backri, Viktor Zólyomi, Colin J. Lambert. 2014-02-24. Electronic properties of linear carbon chains: resolving the controversy. https://doi.org/10.1063/1.4867635

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