Triplet State Absorption in Carbon Nanotubes: A TD−DFT Study

Triplet state absorption in carbon nanotubes: a TD-DFT study.

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 state energies. Like in pi-conjugated polymers, the lowest CNT triplets are spatially localized. These states show strong optical absorption at...

Photoexcitation of the triplet exciton in single wall carbon nanotubes

The carbon nanotube photoexcitation spectrum is dominated by excitonic transitions, rather than interband transitions between continuum states. There are eight distinct excitonic transitions (four singlet and four triplet), each with two-fold degeneracy. Because the triplet excitons are spin polarized with electron and hole spins both pointing in the same direction, they are optically inactive,...

Microwave Absorption Characteristics of Carbon Nanotubes

/3-Carotene triplet state absorption in the near-IR range

The/3-carotene absorption from the lowest triplet state was investigated over a wide spectral range. A new absorption transition in the nearIR region was found. The absorption band exhibited a 0--0 transition at about 8100 cm1 with a low intensity, lower by a factor of approximately 300 than the intensity of the known triplet-triplet absorption in the visible range. The vibronic structure of th...

Carbon Nanotubes – A scientometric study

In contrast to our previous study (Barth & Marx, 2008) dealing with a currently decreasing research field (high-temperature superconductors) we analyzed here a topic which has raised a strongly increasing interest among researchers: research activities around carbon nanotubes (CNTs or NTs). Carbon nanotubes (often named only nanotubes) are graphite sheets rolled up into cylinders with diameters...