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Triplet absorption in carbon nanotubes: a TD-DFT study

Sergei Tretiak
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Abstract

We predict properties of triplet excited states in single-walled carbon nanotubes (CNTs) using a time-dependent density-functional theory (TD-DFT). We show that the lowest triplet state energy in CNTs to be about 0.2-0.3 eV lower than the lowest singlet states. Like in $π$-conjugated polymers, the lowest CNT triplets are spatially localized. These states show strong optical absorption at about 0.5-0.6 eV to the higher lying delocalized triplet states. These results demonstrate striking similarity of the electronic features between CNTs and $π$-conjugated polymers and provide explicit guidelines for spectroscopic detection of CNT triplet states.

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Sergei Tretiak. 2007-02-13. Triplet absorption in carbon nanotubes: a TD-DFT study. https://doi.org/10.1021/nl070355h

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